(first post, hello!)
This is easily the best pointing device that I've ever used. The ergonomics are unmatched by any other product (for a righty anyway). Everything is exactly where you need it, which is pretty nice for a five-button device. Just place your hand on it, and you only need to move your phalanges. I didn't ever experience any wrist pain or fatigue with this product, and I'm the type of guy who has frequently wasted many consecutive hours spaced out in various MMORPGs.
It distresses me that these things were discontinued, cos my unit recently crapped out and my cheapo Logitech Trackman Wheel is a far cry from a proper replacement. I've been creeping around here reading about alternatives, and the CST LaserTRAC has caught my attention. I'm a little turned off by the hefty price tag, though. Plus, it looks clunky, not so comfortable, and the scroll wheel seems a little far out of range. And, geez, for such an expensive product, I'd expect more than 3 buttons. I know you can mod a couple in, but I'm not very talented in that respect. I guess I'll just wait for the new model to come out, or hell, maybe even break down and get a Kensington...