When I first got the mouse and felt it for the first time it felt lighter whem compared to the other mouses I had used. With how light it felt I assumed it was fragile and the parts were cheap and not as durable as other mouses I had used. Thats one thing I was wrong about with this mouse.
I can tell you I've dropped it many times and thought it would be broken but to my surprise it works just like it did when I first used it.
Its Comfort and Ease of Use
The buttons felt easier to click when compared to my logitech mouse that would cause my wrist to get somewhat irratated after clicking for so long. Also 2 additional buttons were on the Microsoft Intellimouse Optical Mouse when compared to other mouses I had used. The 2 extra buttons the mouse has allow you to go back a page with one of the buttons(on the left side) while the other allows you to go forward a page(on the right side). The extra 2 buttons are located below the left and right buttons an average mouse would have. It took some getting use to for me to adjust to the additional buttons on the mouse. Like I said earlier the buttons are easier to click and sometimes I would accidently click the buttons.
Its Frustration and Convenience
Accidently clicking the buttons could be frustrating esspecially the 2 extra buttons as I would accidently click the lower left button after I finished typing a review. I than had to retype a review but smartened up to avoid this so I now type my reviw on notepad and then copy a paste my review. So far I've gotten use to the mouse and accidently click things like that no where near as much now. This actually has became my favorite mouse to use now. Its very convenient just to push the extra buttons and send it back or forward a page. After adding up the numerous times I would go backward or forward on a page the mouses additional buttons save me time
The mouse is very comfortable to use and it also saves time not having to click as many buttons.
Update On Jun 25, 2011: Well its been 18 months now since I started this review and this mouse is still going strong. I can honestly say this is the best mouse I've ever used. With someone whos on the computer as much as I am my wrist never gets tired with how many times I click with this mouse. Also I'm so use to the durability of this mouse that I've actually gotten careless when it comes to dropping it. I just know the mouse is probably going to coninue working even after I drop it. The only time I got worried after dropping it was when I thought it was broken but it wasn't. All I had to do was push the bottem part of the mouse inward and then it started working again. Those are the times when it hit the floor hard. Microsoft really did a great job with this mouse design. I would rate it 5 stars now after useing it for so long.