I'm not really sold on this whole amp modelling thing but I use my Guitar Port a lot for recording and practising. I record into Cuebase SX mainly just to hear and track my progres and to save ideas. You can manipulate the audio file like slow it down it check your accuracy and record yoursefl along with a
backing track. Its then easy to burn it to cd or to my iPod.
Don't get me wrong, I'd never use it for anything but home or studio use and my Marshall's are the only thing I'd use when playing out but imo its a very useful tool. I don't bother with the Live element though, too much $$$ and weak content last time I looked.