I have a G2 which has a great distortion (gain1 is classic, gain2 is modern. They actually sound quite similar but gain2 has way more gain and the overall EQ is boosted) and clean (not a sterile tranny clean, but actually quite a sparkly clean which has a boost function which adds more highs, lows and volume). The G3 version (which I have used in fact) is very similar but instead of being all SS it's hybrid. Same Mosfet poweramp. Only uses the tube as a clipping diode but it still adds warmth as tubes anywhere in the circuit generally do. Isn't very versatile for anything besides metal/hard rock (in which you'll find very versatile. Clean, more clean, gain and more gain!). I have a soundclip of my G2 (on gain1 mode, Randall cab with Vintage 30s).
Here: The G3 is a tad warmer and sounds a little different, but it gives you an idea of how much gain is on this thing considering the gain is on about 6 and it's only on the classic setting.
http://soundclick.com/share?songid=5942267