I flagged a blog post the other day from a news feed where someone implied that they had removed ReSharper 4.0 Beta because they did not agree with the ReSharper 4.0 hints regarding the use of the var keyword. If you install the ReSharper 4.0 beta and don't change any of the Introspection Settings in the options, ReSharper will offer you the hint of using the var keyword when declaring variables, etc. It may seem like a suggestion, warning, or even an error when you see the little squiggle, but hey, it's a hint.
Now the beauty about these little hints, suggestions, etc. is that they teach you a little about what is possible in your programming language. Maybe you didn't realize the var keyword existed and when you could and could not take advantage of it. Better yet, and here is the real kicker, you have the option of adjusting the settings:

Therefore based on your coding standards and beliefs, you have the ability to personally adjust the settings for the various hints, suggestions, warnings, errors, etc. So before you jump into the mistake of un-installing ReSharper ( or any tool ) on such a coding style disagreement, you may want to see if you can adjust the settings to your particular style :)