My Q's are 7ft off the ground and work great. Your NOT making the right decision to use m60's or m80's are right surrounds, you want to use Q's.

M80s VP180 4xM22ow 4xM3ic EP600 2xEP350
AnthemAVM60 Outlaw7700 EmoA500 Epson5040UB FluanceRT85