Hi, I have the G7 mouse, and like it.
However, I am not too sure about its button life, as I have had to return my first one to Logitech as the left button packed up, and it is not sounding too good on this replacement.
I had the first mouse for about 9-10 months before the left button gave way, and I put it down to too much clicking in C&C Generals/Zero Hour
What happened was that if I left clicked on an icon on the desktop, it would just double click it, and other irritations that made the mouse pretty much useless.
Logitech support was excellent after I contacted them. After swapping details (mouse s/n etc) they sent me a replacement from Switzerland (I am in the UK) and I just had to return the USB dongle to complete the transaction.
This second mouse is a few months old, and already I can detect that the left mouse button is not firmly clicking as it should, so maybe the micro switch (or whatever is used) is also on its way out ?
Other than that, I like the mouse, but I wish it had the same number of buttons as my previous MX1000.
The battery swap is very easy and takes seconds to do, but I usually find that I forget to check the battery state before a game, and it always runs out in the middle of a fire-fight
Overall for me, it fits nicely in my hand, the non-slip pads are nice and big, and very responsive. I also like the ability to change the resolution (1-3 built in options) with the press of a button on the fly.
The G5 which I have also used is much the same but wired.
Nice mouse, but I am not sure about its working life.