One of the guys at work has a mx700 for his PC and another for his Mac. He can't use them both at the same time, but otherwise they work fine.
I'm not sure if you can change the 'channel' that it uses. I'll see, I use one at work.
Edit: Didn't work, the channel didn't change. This mouse has been acting funky lately though, the extra buttons on top don't work properly.