Sorry for not being more clear; the 200MB is one of those small metal amps from back in the day. I bought this one used in the mid 80's.
It has a 12" in a small metal cabinet and allows for an extension speaker with the main speaker on or off. It is rated at 100 watts @ 4 ohms. http://www.gallien-krueger.com/manua...-instructions/
It is a great practice amp and can do small coffeehouse type gigs as the speaker is not so efficient especially in a small cabinet.
Today I tried just the power amp section into a Dr. Bass 2x12 with a tweeter.
It was unbelievably loud with the clip light just lighting; easily enough to do a gig with a rock or blues band.
I suppose this amp is too esoteric for a comparison with either the RB or new MB micros but was hoping there was a geezer to two that still had one kicking around.
Ironically, just the amp version was for sale in the classifieds last week.