I personally have Sanyo Eneloop's, and the battery life on the G602 is insane
Always get Sanyo Eneloop's when using wireless mice. Not only do they last but recharging them is relatively quick compared to most on board batt's.
The G602 is quite a good choice, wireless that doesn't need to be charged every day like the G700S .
The fact that the G700s lasts only 8-10 hours of real use makes it a joke IMO.
They had such a good mouse, yet they couldn't afford to give it 2x AA battery slots?
-_-
It has one of the best physical designs & buttons layouts along with features, yet they cripple it's wireless which is what it's all about.
They should just make a G701 and take the G700s and strip out the wireless feature and put in a nice braided cable and make it a good wired mouse.
Cause honestly, there is nothing wrong with that mouse, it just has a seriously gimped single AA battery slot and crappy battery life to boot.