I've got the MX700 and personally love it. When I first got it and started using it, I had to use the mouse for 2 days before it would warn me that it needed recharging (though I could use it for another couple hours after that with no problems). Now it only lasts about 7, maybe 7 hours. One reason I'm looking for a replacement.
I do hate that they dropped some of the buttons. I use both the forward / back buttons, as well as cruise control scrolling ones. It personally seems like the stupidist idea ever to get rid of the buttons. If you don't use them in a game, just disable them, or map several of them to the same function if you keep hitting the wrong one.
I'm just wondering who they get their reviews from to justify removing the buttons, cause it doesn't seem like hardcore gamers or power users.
That said, still want the G7 for Christmas (Not having to fight the dragging cable totally makes the wireless worth it)