I've gone through a variety of different mice over the years. I'm not a gamer. I want comfort, reliability, a scroll wheel, and a real cord. My most recent Logitech purchase, a few years ago, was an earlier version of the M500 (without the "hyper" scrolling thing). After two years, the thin rubber layer had worn off in the areas where my fingers frequently touched it. The mouse buttons didn't always click right. Etc.

Much as I hate dealing with batteries, I'm currently trying the Apple touchpad thing on my computers. I don't use all the crazy gestures, and I had to cobble together something of a wrist pad from a folded t-shirt to make it comfortable on my work desk. Still, it's a very solid device. It's just too bad it doesn't have a USB cord.