I had a couple of the bigger RB amps, but only used a single 2x10 cab most of the time. You can't really throw 400-500 watts into a 2x10. I sold those off and got a 400RBIII. The low end isn't as thick at the MB digital series, but they are sound really good. It allows me to get the amp in it's sweet spot at much lower power. I found even better sound with I experiemented with different 2x10 cabinets. Some brought out the growl even more...