You are corect in pairing the 400 with the M22's it does sound incredibly good, but as you already have the M80s, I wouldn't sell them off to get the M22/EP400 combo. The M80s are a better speaker IMO. If space was a concern then yes going to the M22/EP400 set up would be a very good substitute for the M80's, especially for a music only system.

Jason
M80 v2
VP160 v3
QS8 v2
PB13 Ultra
Denon 3808
Samsung 85" Q70