Just my 2 cents and HO.

I have a M60ti, VP150, QS8, Velodyne DLS-4000 Sub,Yamaha RX-V2400, 65" mits in a room 15 x 18'

Sounds great and I don't feel like its a compromise. For the M60 / M80 diff you can get the QS8 and maybe a decent used sub until you are ready. My DLS-4000 was $ 299 I think it was the last one he had before the redesign. I would prefer to have an EP600 but not in my budget. If I had to wait for a sub I could live with the bass from teh M60s.