I have been researching different batteries for my W510 ThinkPad and have come to the conclusion that the ThinkPad Battery 27 + + 9 Cell is the best available one. Can anyone tell me the expected hours this battery lasts? Currently my battery lasts about 2 hours. I was looking for a battery with a serious life time that could help me as I go away to college. Some of the reviews and what not on OTHER batteries listed the life time 10.9 hours for the top batteries, however, this particular one did not list the life time in hours. Thanks so much!