I used the Spyder2Pro for almost a year then it developed a nasty habit of losing the USB driver for the sensor. I'd re-install, get one monitor profiled(maybe) and then lose it when I unplugged the sensor. DataColor's tech service was, shall we say "less than useful" and leave it at that

. I'm fairly computer savvy, familiar with Windoze, and my home-built PC runs reliably and well, so I'm pretty sure it wasn't a hardware problem.
I replaced it with the Eye One Display 2, have had no problems and like the software better.
Bill