Disclaimer The opinions expressed herein are my own personal opinions and do not represent my employer's view in anyway.
Resharper is great. It includes so many neat tools and shortcuts that it really is hard to argue that it's the best Visual Studio productivity tool available today.
So - why do I hate it so much?
1: A lot of the tools are better versions of the standard Visual Studio versions - refactoring, templates/snippets etc. I find the VS versions good enough.
2: There's 3 pages of keyboard short cuts to remember if you want to use Resharper effectively. I have enough trouble remembering Ctrl+C to copy.
3: It's sooooo f-ing slow! VS runs like a complete dog when Resharper is installed. All those productivity gains are pointless if you are waiting for VS to respond.
4: It's noisy. I like VS clean and simple. I dont like all the Reshaper crap over the screen interfering with my train of thought.
5: It's a little buggy - well, I cant say this for sure, but I think it suffers from trying to be too clever and sometimes it gets things wrong, especially with ASP.Net tags.
So, this time I managed to keep it on my machine for 3 days before removing it. I'll try it again in another couple of versions.