I installed CodeRush into one of machines just a while ago and it didn't take me long to decide to uninstall it and have Resharper instead [more](have resharper on another machine).
CodeRush have more "eyecandy" as they say, looks more pleasing to the eye (subjectively of course), has very powerful use of templates (type pi and will produce a private int property with an underlying private field), the code flow/break statement, clear way of indicating scope (code blocks) and I haven't explored yet but they do have some code metrics features.
I don' t know if I'm using the right terms for these features but I think resharper's analysis and testing support is better. Plus, I feel that CodeRush is being too smart for me and I would stick with resharper for now and explore its Live Templates features to be close to that of CodeRush.
CodeRush is actually a code generation tool, while resharper is more of a refactoring tool (thus better matched with DexExpress' Refactor – makers of CodeRush). But IMHO resharper is more than that and probably safe to say is even better with CodeRush and Refactor combined. It could be because I've used resharper first (though been only a week) and most of the time it wins over CR in reviews but then again this is just my opinion.
Plus not to forget that if you consider Resharper's pricing, I don't have to think twice for now 😀 and go with Resharper.
Ideally, it would be nice to run them both but I don't want to mess with the machines I have for now. Leaving it for a later post if I do find time to try them both together. For now, uninstalling CR here and having R# in place. I wonder what others think?