It becomes a personal preference at this point I found the M60s vocals to take a back seat to the music ever so slightly directly compared to the M80s. Other than that and the slightly lower/smoother bass, they are almost identical. I would never go back to the M60 after hearing the M80s and now owning.

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