diff --git a/json-path/src/main/java/com/jayway/jsonpath/internal/CharacterIndex.java b/json-path/src/main/java/com/jayway/jsonpath/internal/CharacterIndex.java
index 1aa286799..3193bcf49 100644
--- a/json-path/src/main/java/com/jayway/jsonpath/internal/CharacterIndex.java
+++ b/json-path/src/main/java/com/jayway/jsonpath/internal/CharacterIndex.java
@@ -220,16 +220,18 @@ public void readSignificantChar(char c) {
         incrementPosition(1);
     }
 
-    public void readSignificantSubSequence(CharSequence s) {
+    // true if successful, false if invalid path
+    public boolean readSignificantSubSequence(CharSequence s) {
         skipBlanks();
         if (! inBounds(position + s.length() - 1)) {
-            throw new InvalidPathException(String.format("End of string reached while expecting: %s", s));
+            return false;
         }
         if (! subSequence(position, position + s.length()).equals(s)) {
-            throw new InvalidPathException(String.format("Expected: %s", s));
+             return false;
         }
 
         incrementPosition(s.length());
+        return true;
     }
 
     public int indexOfPreviousSignificantChar(int startPosition){
@@ -314,4 +316,4 @@ public CharacterIndex trim() {
         skipBlanksAtEnd();
         return this;
     }
-}
\ No newline at end of file
+}
diff --git a/json-path/src/main/java/com/jayway/jsonpath/internal/JsonContext.java b/json-path/src/main/java/com/jayway/jsonpath/internal/JsonContext.java
index 731473348..ad93e747e 100644
--- a/json-path/src/main/java/com/jayway/jsonpath/internal/JsonContext.java
+++ b/json-path/src/main/java/com/jayway/jsonpath/internal/JsonContext.java
@@ -216,7 +216,7 @@ public DocumentContext put(JsonPath path, String key, Object value) {
 
     private JsonPath pathFromCache(String path, Predicate[] filters) {
         Cache cache = CacheProvider.getCache();
-        String cacheKey = Utils.concat(path, new LinkedList<Predicate>(asList(filters)).toString());
+        String cacheKey = path + new LinkedList<Predicate>(asList(filters)).toString();
         JsonPath jsonPath = cache.get(cacheKey);
         if (jsonPath == null) {
             jsonPath = compile(path, filters);
diff --git a/json-path/src/main/java/com/jayway/jsonpath/internal/filter/EvaluatorFactory.java b/json-path/src/main/java/com/jayway/jsonpath/internal/filter/EvaluatorFactory.java
index ac47274a7..5dedc54c1 100644
--- a/json-path/src/main/java/com/jayway/jsonpath/internal/filter/EvaluatorFactory.java
+++ b/json-path/src/main/java/com/jayway/jsonpath/internal/filter/EvaluatorFactory.java
@@ -91,7 +91,13 @@ public boolean evaluate(ValueNode left, ValueNode right, Predicate.PredicateCont
     private static class LessThanEvaluator implements Evaluator {
         @Override
         public boolean evaluate(ValueNode left, ValueNode right, Predicate.PredicateContext ctx) {
-            if(left.isNumberNode() && right.isNumberNode()){
+            if(left.isStringNode() && right.isNumberNode()) {
+                return Double.parseDouble(left.asStringNode().getString()) < right.asNumberNode().getNumber().doubleValue();
+            }
+            else if(left.isNumberNode() && right.isStringNode()) {
+                return left.asNumberNode().getNumber().doubleValue() < Double.parseDouble(right.asStringNode().getString());
+            }
+            else if(left.isNumberNode() && right.isNumberNode()){
                 return left.asNumberNode().getNumber().compareTo(right.asNumberNode().getNumber()) < 0;
             } if(left.isStringNode() && right.isStringNode()){
                 return left.asStringNode().getString().compareTo(right.asStringNode().getString()) < 0;
@@ -103,7 +109,13 @@ public boolean evaluate(ValueNode left, ValueNode right, Predicate.PredicateCont
     private static class LessThanEqualsEvaluator implements Evaluator {
         @Override
         public boolean evaluate(ValueNode left, ValueNode right, Predicate.PredicateContext ctx) {
-            if(left.isNumberNode() && right.isNumberNode()){
+            if(left.isStringNode() && right.isNumberNode()) {
+                return Double.parseDouble(left.asStringNode().getString()) <= right.asNumberNode().getNumber().doubleValue();
+            }
+            else if(left.isNumberNode() && right.isStringNode()) {
+                return left.asNumberNode().getNumber().doubleValue() <= Double.parseDouble(right.asStringNode().getString());
+            }
+            else if(left.isNumberNode() && right.isNumberNode()){
                 return left.asNumberNode().getNumber().compareTo(right.asNumberNode().getNumber()) <= 0;
             } if(left.isStringNode() && right.isStringNode()){
                 return left.asStringNode().getString().compareTo(right.asStringNode().getString()) <= 0;
@@ -115,9 +127,16 @@ public boolean evaluate(ValueNode left, ValueNode right, Predicate.PredicateCont
     private static class GreaterThanEvaluator implements Evaluator {
         @Override
         public boolean evaluate(ValueNode left, ValueNode right, Predicate.PredicateContext ctx) {
-            if(left.isNumberNode() && right.isNumberNode()){
+            if(left.isStringNode() && right.isNumberNode()) {
+                return Double.parseDouble(left.asStringNode().getString()) > right.asNumberNode().getNumber().doubleValue();
+            }
+            else if(left.isNumberNode() && right.isStringNode()) {
+                return left.asNumberNode().getNumber().doubleValue() > Double.parseDouble(right.asStringNode().getString());
+            }
+            else if(left.isNumberNode() && right.isNumberNode()){
                 return left.asNumberNode().getNumber().compareTo(right.asNumberNode().getNumber()) > 0;
-            } else if(left.isStringNode() && right.isStringNode()){
+            }
+            else if(left.isStringNode() && right.isStringNode()){
                 return left.asStringNode().getString().compareTo(right.asStringNode().getString()) > 0;
             }
             return false;
@@ -127,7 +146,13 @@ public boolean evaluate(ValueNode left, ValueNode right, Predicate.PredicateCont
     private static class GreaterThanEqualsEvaluator implements Evaluator {
         @Override
         public boolean evaluate(ValueNode left, ValueNode right, Predicate.PredicateContext ctx) {
-            if(left.isNumberNode() && right.isNumberNode()){
+            if(left.isStringNode() && right.isNumberNode()) {
+                return Double.parseDouble(left.asStringNode().getString()) >= right.asNumberNode().getNumber().doubleValue();
+            }
+            else if(left.isNumberNode() && right.isStringNode()) {
+                return left.asNumberNode().getNumber().doubleValue() >= Double.parseDouble(right.asStringNode().getString());
+            }
+            else if(left.isNumberNode() && right.isNumberNode()){
                 return left.asNumberNode().getNumber().compareTo(right.asNumberNode().getNumber()) >= 0;
             } else if(left.isStringNode() && right.isStringNode()){
                 return left.asStringNode().getString().compareTo(right.asStringNode().getString()) >= 0;
diff --git a/json-path/src/main/java/com/jayway/jsonpath/internal/filter/FilterCompiler.java b/json-path/src/main/java/com/jayway/jsonpath/internal/filter/FilterCompiler.java
index 67b512e41..bfdc0e473 100644
--- a/json-path/src/main/java/com/jayway/jsonpath/internal/filter/FilterCompiler.java
+++ b/json-path/src/main/java/com/jayway/jsonpath/internal/filter/FilterCompiler.java
@@ -132,6 +132,13 @@ private ExpressionNode readLogicalOR() {
 
         while (true) {
             int savepoint = filter.position();
+            if (filter.readSignificantSubSequence(LogicalOperator.OR.getOperatorString()))
+                ops.add(readLogicalAND());
+            else {
+                filter.setPosition(savepoint);
+                break;
+            }
+/*
             try {
                 filter.readSignificantSubSequence(LogicalOperator.OR.getOperatorString());
                 ops.add(readLogicalAND());
@@ -140,6 +147,7 @@ private ExpressionNode readLogicalOR() {
                 filter.setPosition(savepoint);
                 break;
             }
+            */
         }
 
         return 1 == ops.size() ? ops.get(0) : LogicalExpressionNode.createLogicalOr(ops);
@@ -152,6 +160,13 @@ private ExpressionNode readLogicalAND() {
 
         while (true) {
             int savepoint = filter.position();
+            if (filter.readSignificantSubSequence(LogicalOperator.AND.getOperatorString()))
+            ops.add(readLogicalANDOperand());
+            else {
+                filter.setPosition(savepoint);
+                break;
+            }
+/*
             try {
                 filter.readSignificantSubSequence(LogicalOperator.AND.getOperatorString());
                 ops.add(readLogicalANDOperand());
@@ -160,6 +175,7 @@ private ExpressionNode readLogicalAND() {
                 filter.setPosition(savepoint);
                 break;
             }
+            */
         }
 
         return 1 == ops.size() ? ops.get(0) : LogicalExpressionNode.createLogicalAnd(ops);
diff --git a/json-path/src/main/java/com/jayway/jsonpath/internal/filter/ValueNode.java b/json-path/src/main/java/com/jayway/jsonpath/internal/filter/ValueNode.java
index d1619c453..0dc7418bd 100644
--- a/json-path/src/main/java/com/jayway/jsonpath/internal/filter/ValueNode.java
+++ b/json-path/src/main/java/com/jayway/jsonpath/internal/filter/ValueNode.java
@@ -814,7 +814,7 @@ public PathNode asExistsCheck(boolean shouldExist) {
 
         @Override
         public String toString() {
-            return existsCheck && ! shouldExist ? Utils.concat("!" , path.toString()) : path.toString();
+            return existsCheck && ! shouldExist ? ('!' + path.toString()) : path.toString();
         }
 
         public ValueNode evaluate(Predicate.PredicateContext ctx) {
diff --git a/json-path/src/main/java/com/jayway/jsonpath/internal/path/PathToken.java b/json-path/src/main/java/com/jayway/jsonpath/internal/path/PathToken.java
index 5a5046d84..b9c515a28 100644
--- a/json-path/src/main/java/com/jayway/jsonpath/internal/path/PathToken.java
+++ b/json-path/src/main/java/com/jayway/jsonpath/internal/path/PathToken.java
@@ -40,7 +40,7 @@ void handleObjectProperty(String currentPath, Object model, EvaluationContextImp
 
         if(properties.size() == 1) {
             String property = properties.get(0);
-            String evalPath = Utils.concat(currentPath, "['", property, "']");
+            String evalPath = currentPath + "['" + property + "']";
             Object propertyVal = readObjectProperty(property, model, ctx);
             if(propertyVal == JsonProvider.UNDEFINED){
                 // Conditions below heavily depend on current token type (and its logic) and are not "universal",
@@ -123,7 +123,7 @@ private static Object readObjectProperty(String property, Object model, Evaluati
 
 
     protected void handleArrayIndex(int index, String currentPath, Object model, EvaluationContextImpl ctx) {
-        String evalPath = Utils.concat(currentPath, "[", String.valueOf(index), "]");
+        String evalPath = currentPath + "[" + index + "]";
         PathRef pathRef = ctx.forUpdate() ? PathRef.create(model, index) : PathRef.NO_OP;
         int effectiveIndex = index < 0 ? ctx.jsonProvider().length(model) + index : index;
         try {