Had a couple of bluetooth mice, and this one is by far the best. Was a little bit apprehensive due to the few negative reviews, but bought it anyway and haven't regretted it. Very quick and easy to set-up, and a quality feel to the mouse itself (with Duracell batteries included - don't know why, but branded batteries always make me feel a bit better for some reason!) The mouse is very responsive, and comes to life very quickly after periods of user inactivity (which can't be said for some of the other mice I've owned). Its a little smaller than I was expecting, but after a day or so using it I've realised that the shape and size are perfect, and I've switched to using the mouse full-time, rather than reverting to the one attached to my docking station when I'm back at my desk. Not normally a massive fan of Microsoft, but this is a great product.