I love it. I've had one for a few years and it's never let me down. I haven't been very good to it either. Left it out in a cold garage over the winter. Dropped it a couple of times. It's a solid performer. Sounds great too. My friend who owns an RB700 says they sound exactly the same. I think the MB is a slight notch below the RB in sound quality, but only a small notch, and a fair trade for the lightweight package for sure. It definitely has GK tone. Worth noting though, to me the amp can be a bit sterile. It's a very clean, hi-fi modern tone. Great for slap bass, funk tunes and anything requiring a nice clean tone, but for my rock gigs I picked up a Mesa M6 Carbine. I like being able to drive the tube preamp to distortion and get a big rock tone. My experience is with the grey solid state version of the amp. I understand there's a tube hybrid version as well, which has been compared to the M6 as far as tonal characteristics. I love my MB500 so much, I would have gladly bought the tube version if I could find one to test drive, but nobody had one to demo in the entire state of Maine, so I wound up with the Mesa. Worth looking into though, as I'm sure it can get the clean tones and nice GK growl, and maybe a bit more grit with that tube preamp.
