John Garcia
Senior HTF Member
Dual 5-1/4s will give you more sound than a single 6-1/2, though not lower response (looks like they are the same -3dB, but the M22 has a +1dB sensitivity). More air is moved, and the higher sensitivity will allow them to play louder. My mains are dual 5-1/4 I'm very pleased with their SPL.