After watching the first screencast that Aaron presented on Vim, I thought I would check it out. The first day was a little uncomfortable, 2 weeks later I am happy to report that I concur with Aaron's statement, which is also what I say to people who were not using ReSharper:
"I could not use studio without it"
ReSharper + Viemu is the ultimate killer combo for increasing your keyboarding productivity. The fact that you can keep your hands on home row to do the majority of your navigation is a huge plus. The core command set does not take a lot of time to learn, you just have to stick with it so that it becomes second nature. Once it does you will be "yanking", "pasting", "changing" ..... up your code in ways that now make studio seem extremely cumbersome.
As with picking up any new tool/technique there is a period of ramp up that you have to go through. It was a 2 week road trip where I could not use my mouse, that forced me to learn all of the keyboard shortcuts that I needed to get around windows, studio etc with efficiency. After that 2 week period I realized that there were very few things that I actually needed to reach for the mouse for (game playing aside).
To dive in full force, I also purchased the Vim integration that works in Outlook and Word. That way I can completely immerse myself in the Vim experience.
I encourage you to check it out and give it an honest and open attempt. You might surprise yourself with the results.