It's easy to use, I can see errors in my app/code without even loading up any codebase or web site that uses this service. Great for finding issues before they happen! Also very helpful with automated tests as well!! There isn't anything i dislike about ray gun aside from maybe some of its features being not quite what we need at times (but thats because our needs change). We've used their free version first, so there is nothing wrong with using them if you are just looking into testing your applications. You cannot have too many tools like these when working on large projects such as ours. It helps us find bugs faster than ever before!