Sorry to hear about your pain. I don't have it yet - but someone once told me it's not if I'll have RSI, but when.
I use an Apple Mighty Mouse Bluetooth at home (left hand), but mainly a SwiftPoint GT (right hand) at work and elsewhere.
My favorite pointing devices were a giant trackball (a decade or more ago, I don't even remember who made it - but it was awesome, and it was for the Mac with ADB), followed by the Apple trackpads (any of them, they're mostly great), then the SwiftPoint GT.
I find the lack of 360 scrolling (done correctly - i.e. moves a proportional screen distance) one of my biggest irritations with non-Mac platforms.
I was actually wondering if we could program the green function layer with the legacy numeric pad arrows so I could use Mouse Keys on Windows. Not sure how that would work out. I didn't like it much when I had that on my Mac with System 7, but then again any cursor movement compared to the huge trackball just seemed inferior. I might like it if it meant never having to take my hands off the home row.
The TextBlade with its ability to pair with multiple devices is is really amazing! I wish my SwiftPoint GT could do that. I leave it paired to my iPad, and use the included proprietary SwiftPoint dongle with my work PC, which thankfully overrides the Bluetooth pairing so I don't have to un-pair it.