I have been using Resharper for about 3 weeks now. There are a lot of very very cool things there:

• The refactoring methods are a must – I would hate to go back to the VS2005 refactoring now. A lot more flexibility, a lot faster, and a lot of things that are simply not possible with VS2005 (eg renaming namespaces)
• Ability to do quick templates – they are like macros except easier to set up.
• The automatic error notification. This might be the biggest productivity improvement – it is a lot better than VS at reporting errors at edit time.

That being said, there are still quite a few annoyances and I am still deciding whether it is worth putting up with them:

• The VS keybindings are well, not there anymore. This makes it twice as hard to switch between machines that don’t have Resharper installed. I wish they had tried to keep them somewhat similar
• My intellisense now seems to bug out once in a while. Usually restarting VS fixes it, sometimes I have to turn it off and back on. Sadly I am unable to get Resharper’s built-in intellisense to work reliably, which makes using the templates a bit more tedious.
• It slows down startup, a bit. Happens mostly in the background so that’s not major
• It creates a bunch of files: resharper, resharper.user, resharper folder… I wish they kept it in just one folder rather than polluting mine.

Oh well, still an awesome tool. Once the eval runs out I’ll probably give a try to Coderush. Then the fun part will be to try and get my boss to pay for it, hah!!