In my case I wouldn't do it because even if it was loud enough, I would loose the acoustic coupling of both speakers and I would then try to compensate for that with EQ which would then be pushing the cab even more and still not sound the same. So IMHO two cabs always to give me the tone I want, the volume I want and the safety I want.Not even loud enough for practice, huh? The stack looks killer, though!
So if the DB 500 at 8 ohms, which would be putting out 250-300 watts, isn't loud enough to do anything, I guess the DB 200, even at 4 ohms, is pretty much useless. That seems to be what people are saying.