This particular mouse I give 4.5 stars. Both mouse at work (and the one I own back home) are really relaxing to grasp and use. When you let your hand put covering the mouse, it positions your palm in what I believe as a "shake hand" position rather of flat at the table. This can take about a week to get used to, but afterward it really is fantastic simply how much more effective that position is. It's a mouse that features a bit of "meat" to it, so it really is suit my large hand to grasp on to.
The mouse has a smooth-scrolling wheel, perfect for productiveness (while bad for FPS video games). Pressing the scroll-wheel to get a middle-button result is very hard to perform using this particular wheel, but that may not be much of a difficulty, as one from the 2 thumb buttons can be reassigned into the middle button function through the Microsoft application.
The keyboard I give 3.5 stars. It really is splendidly convenient and comfortable to use, nonetheless the "wireless" area of the equation makes it work somewhat unevenly from time to time. I type very quickly, and the keyboard will once in a while just lose keystrokes... or momentarily stop acquiring input altogether. I much prefer my home setup, where I've the Microsoft Natural Mouse attached cordelessly, and the Microsoft Natural Keyboard hooked up via USB.