First off, you have to take RSI really seriously, because it becomes chronic and you can risk agonizing pain, or even worse, as one of my friends, not being able to use e.g. one of your arms anymore.
When I started in the IT industry as a pro back in '97 I had a two year project with intense mouse usage. The result was a chronic injury in my right shoulder that will never go away. Since then I simply (unfortunately) cannot use a regular mouse any more. Even using one for just an hour and I will feel it for the next week. So since '99 I have used a Contour Rollermouse, it’s really the only thing I can use and I recommend it. It’s not cheap but it works well. If you have no issues in your arms or shoulders, the second best option would probably be something like the Apple “magic” trackpad.
Now, things like that are not “the best mouse for VCV”, that would be a regular mouse, but you can’t use that anymore, seriously! But it works fine for everything, you just have to get used to slightly less efficiency.
Sorry to be the bearer of bad news but there it is. You cannot cheat this one, trust me here!