I have that mouse. I've been using it for about 4 years, not one major problem. Nowadays, the batteries tend to get warm when I recharge them. But that's probably because I've done over 1000+ recharge cycles on the batteries that came with the mouse.
I recently retired that mouse for an MX Revolution. A well deserved retirement I might add. Cosmetically, the mouse looks quite worn out; you would know exactly where my fingers were when I held the mouse. Functionality wise, the main reason why I had to retire it, when I hold the left button and drag, it would sometimes think I released the button during mid-drag. Quite annoying when I'm moving files on my computer and they're not in the directory I wanted them to be.