I'm using mine right now, and love it. When I started experiencing forearm pain a few months ago, I bought several vertical mice from different manufacturers.

I'm using mine right now, and love it. When I started experiencing forearm pain a few months ago, I bought several vertical mice from different manufacturers. The Anker was the clear winner for me. It fits the best in my hand and is shaped so I can easily lift it up and re-position it.