Josh:

It's worked out very well so far. I've only got moderate RSI issues, but back in November, I tried my hand at NaNoWriMo and two weeks in my hands/wrists pretty much locked up. I took a flyer on the Touchstream, getting one for my home computer, and it started to help so I picked up a second one to use at work (I also switched over to a Dvorak layout at the same time), In a week my wrists were back to normal.

Not having to reach for and use a mouse (notorious wrist wreckers) was a big, big help. They might look to be expensive, but I feel they're worth every penny (and if it doesn't work out for you, they have very good resale value on ebay).