Been beaten several times and been away for a while but wondering why people put M2i instead of M22ti for rear surround?

I was planning on this system for my step father:

25x25 room

Amp: Denon 3805
Front: M80's
Center: VP150
Rear: QS8
Rear surround: M22ti -- or M2 -- or QS8 ?

He's listening 85% HT, 15% Music but when he listens to music, he's psycho and listen to it very loud in 7 channels. Well balanced system or he should really consider a stereo amp for driving the M80's.