3SpeedChicken: I've actually never messed with tube substitution in any of my amps. The 6V6's sound like they might be pretty cool!
I actually play in a country/rock cover band full-time and have been using the "Roadster" for the last few months with great success. Even at low gain settings, it's a tad "too much" for the traditional stuff I have to play, but I'm digging it exactly for that reason. It's different than the norm, which I've grown tired of. It does sound killer for the Big & Rich type of stuff though!
As far as getting real "Classic" tones out of the Roadster? I'm not sure? To me, none of the dual recto type amps really hit the mark on that because of the type of distortion and gain that is inherent to them. I know it's subjective, but when I think of "Classic" or such tones, I think of amps like, DR Z, Fuchs, non-master Marshalls, Fender twins, etc. etc. I also own a Stiletto and have played through numerous Lonestar's and though they come closest to the actual "Brown Sound" there's still something missing that I can not only hear, but feel in my pick attack when trying to emulate more "Classic" type tones. I'm not technical enough to expand with details, it's just a feel thing for me.
BTW I'm not baggin on your opinion or anything, I'm just trying to clarify mine.
Mesa kick's *** in a live setting and cut's through the bottom end band mud better than anything else I've used. One thing I've learned being the tone-freak I am is that trying to micromanage tone in a live setting is a waste of time. There are so many other factors that come into play i.e. crappy or great FOH techs, crummy or great room dynamics, etc. etc. Nowaday's I just dial in a couple of good sounds and worry more about playing well and putting on a good performance. I don't know how many times I've had crummy stage sound with killer front of house sound or vice-versa. When I quit trying to treat the stage like the studio, it all became a lot more fun.
peace all,
-d