Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Another Great Erganomic Product - Yay Microsoft!

Microsoft Erganomic products are the only reason I can sit at my desk all day on the computer. I have been using this mouse for a few weeks now and so far it is working great. I had a lot of pain in the muscle next to my right shoulder blade that caused painful headaches. This product has given me a lot of relief from that. Don't worry about the slanted design, you will get used to it pretty quickly. I am running it on Windows XP and it was easy to install. Overall this is a great product. I use it everyday all day at work and so its definately worth the price for me.I am giving it 4 stars instead of 5 though because the batteries it came with ran out in 2 weeks. So either it came with old batteries or it eats them =/. I bought a pack of re-chargeables and keep 2 and the charger at my desk to swap out when needed.