Well simply in principal, the fact that the MR modles are billed as Mackie's "affordable" line, and that it has some sort of built in room correction (probably pretty crappy), I tend to think it's trying to make up for sub-par performance with bells and whistles, so I'd say BX8a's between the two (though I plan on getting Yamaha MSP5's, cuz though they have a smaller speaker and less power, they seem to be more about quality instead of quantity of power)