Summary: Nice compact shape, but still large enough to be considered a "real" mouse. The wheel doesn't have incremental detents, so is smoother to use for scrolling than others. All in all, a very nice device and worth the modest price.
Summary: I've been through various iterations of the Microsoft comfort mice. I then went through a Logitech phase, which was less comfortable. I finally settled on this one. I have regular-sized hands for a 6'2" man and this mouse is as comfortable as any I have used. I'm on the computer all day at work, and often for much of the evening at home and this mouse causes no fatigue whatsoever.
Summary: I like this mouse. It works and it is reasonably sensitive. The blue light isn't annoying in the dark. All the buttons are responsive. The scroll wheel doesn't have the clicking feeling. That is not a deal breaker but I do prefer the ones that have that clicking feeling. Also with the clicking thing, it's easier to push the middle click without rolling the wheel. The two side buttons are good.
Summary: I have used a MS Mouse 5000 for the past 3 years. I use it a lot.. I think more than most people. My old one is still working great, but wanted a new one, and use the old one with my laptop now. Great quality for the price!