I was pretty upset that my update to 2.0 failed, it eventually worked trying loads of different USB ports, but I've never had a problem like that with any piece of kit (H9, Tc electronic etc). I think there is a problem somewhere in the driver as it can disconnect randomly as well.
BUT, as for sound, I'm blown away with it. Through my new HD600s (another £200 in the money pit !) it's exceptional, and I'm not easily thrilled. Yes, the pitch shifting could be better, and I've been spoiled by BigSky reverbs, but this thing is absolutely brilliant. Love it, well done Line6. Can't believe modelling has come so far.