Not sure what was meant by the 90% comments. For me, I can get a pretty similar tone from any of the cleans or any of the high gains. the difference for me is feel. feel affects my style as much as tone. So it is not all about the tone of the amp but what it takes to get that tone. Same with guitars and pick ups. I don't want this to sound new age-y or nuthin' but guitars and amps kind of tell me how to play them and that takes a while to get to.
I have certain mics that sound marginal with one acoustic guitar but just shine on a different one. My vintage strat sounds like **** with the XMG but is stunning on the SuperClean. Kind of opposite with my JEM. Then again, sometimes when I change pick ups, I end up changing amps as the sound can be similar but it feels different. I love having so many options with the MTS stuff.