Just make sure that you leave enough room to have the M80s well away from the wall (say a foot and a half behind them or more). The difference between M60 and M80 isn't huge in that regard, just that the M80 is a couple of inches deeper so the fronts will be further out in the room.
If you have them too close to the wall, in many rooms you get more bass reinforcement than the average listener wants.
M60ti, VP180, QS8, M2ti, EP500, PC-Plus 20-39
M5HP, M40ti, Sierra-1
LFR1100 active, ADA1500-4 and -8
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