IMHO I prefer CodeRush
VS2010 version is missing ... Very stable, very effective.
Update: CodeRush also looks cheaper. The R # r commercial license is $ 349, where since CodeRush is $ 249, it drops to $ 99 when upgrading
All that said is a very personal decision. It will depend on what you are after.
Below is a link to another answer that I gave regarding the things to consider when deciding between such tools.
Comparison of developer productivity tools
Rory Becker May 04 '10 at 2:06 a.m. 2010-05-04 14:06
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