To replace my MX performance
Compared to the MX, it lacks a bit of support for my palm, especially on the right (minus the star, I was hoping for the same support).
Otherwise, it's a very good, responsive mouse, and the click of the two buttons is smoother than my previous one (10 years of loyal service, I've eaten the rubber off my thumb).
After a week's use, I still haven't needed to recharge the Lipo (it was fully charged when I opened it).
The two buttons, Backward & Forward, fit nicely under the thumb.