I had a coworker load what i think was re-sharper and he unloaded it as he said it made the code edit window very slow.
he is a fast typer of code.
It is very much a benifits against hinderance thing. If you are going to install something that inspects all you code, all the time, then you are going to take a performance hit, but the benefits for me, far outweigh a slightly sluggish UI. If you
have issues with resharper, then you can turn code inspection off, and run it once a week.
I know one of my devs does not use resharper and even he is experiencing crashes on XP. Unfortunately the place I work for has a policy of wiping windows 7 off, and replacing it with XP, that is