The V220 has a nice ergonomic feel; particularly, I love the rubberized grip on the sides. The mouse is gorgeous! Extremely responsive. It is available in many colors; gray is nice, also in blue, red, pink, purple, white, yellow. It is intended for use on laptops which explains its smaller size. I got another Logitech mouse, the V200 which I love especially with the battery that last almost forever which I still use. Hence, I did not hesitate to grab another one from the same manufacturer once I saw this one on sale on a major national chain store. This one claims to have a battery life for a single AA for around 6 months. Having owned the V200, I absolutely have no doubt it can do the same (I will update this post if I find it otherwise). The pack includes one Duracell AA, so it is ready to use out of the box. It also has an on/off button at the bottom which I never used on the V200. I just let it in the on position all the time and it wakes up in a second as soon as I touch it again. I don't even notice any difference in the longevity of the battery juice.
There is a button at the bottom to release the battery compartment. It does not have a spring which usually tells you where the negative end of the battery goes, but it is clearly marked on the compartment the way it should be positioned. The battery is situated a little funny, which is diagonally. The wheel serves as another button which is very useful for me. If you need to travel with it, the USB dongle has a special niche at the bottom and it automatically shuts off the mouse once it is snapped into place.
Pros: - Incredible battery life - Performance - Shape and looks