I'm not really one to overstate my feelings with the Axe FX II, but man I am loving this update. I have updated to 12.03, and all the betas, but I haven't actually got to play until this release of 12.04 beta. The master volume responds amazing, it is so cool. I just played into the stock Hiwatt preset(preset 11 I believe), which I tweaked, and into the USA lead which I also tweaked. I never used to use the Hiwatt because I never like how it sounded, but with this beta and my Tele, it sounds stellar. The USA lead has always been one of my favorites, esp. with my PRS, but I could never get a great sound with my Tele, but tonight it was great. USA Lead, with the low res and low res frequency tweaked, a little but of thunk, 5 band mesa eq, and a compressor for low volume sustain and I was in heaven! I usually don't always notice huge improvements in every firmware, but this one really is the bee's knees! Oh, and btw I could not notice any change in tone whatsoever when changing power tube, with MV low and high, etc. Maybe it is because I wasn't playing loud?