So, im thinking of picking up a second hand AD50VT-XL
from a friend, i looked it up on the website,
and, it said 50 watts RMS, now im a n00b as far
as tube amps go, i know this amp is hybrid, with
(a) tube(s) in the power amp section.

So i was wondering, is the "50 watt RMS" based on
SS watts? or tube watts?

and, could somebody give me some info on
the reliablity of this amp?
First off, it's pretty much an SS amp with a tube in the preamp section (more for gimmicks than anything) The 50 watts is based on how much power it makes. It uses a ss power section, so it's nothing like a tube amp. It would probably have enough power to jam, and maybe for gigs. It's really made to be a practice amp though.
I don't give a shit if you listen to me or not
i have the VT model....and i've never had it passed half volume when doing practices...and not much louder when gigging...unless something else is changed, i think it's be loud enough