Needed a replacement for a couple of unreliable Trust mice, so went for this. Fits snugly into my (rather large) hand and is solidly built. All the extra software you can download is a bit unnecessary, but you can take or leave it, as you choose.
It has a couple of faults, which Microsoft should take note of: 1. The location of the laser is towards the back of the mouse, which takes a bit of getting used-to. 2. The 'free-rolling' nature of the wheel is a bit of an annoyance for general use, but it's a complete disaster if you also use it for gaming: it's impossible to scroll accurately from one item - or weapon - to the next, which sometimes results in my sudden - and unexpected - demise, during a gaming session.
But, despite its faults, I still like it - and I'm still using it.