The MA-7 and 15 powered monitors look very nice. I would think the MA-7 is similar to the MA-8. Since the MA-15 is a stereo pair, they can't be identical to the MA-12, but the Roland site does give specs for comparison.
http://www.roland.com/products/en/MA-15D/brochures.html [This message has been edited by cassp (edited 12-28-2007).]