I think that the name should be far from M80. Calling the 2 M80's, plus or minus a letter, would be too confusing to most everybody.
That's why I like the new tier with a completely different name. Something short, like the Viola series.
Give each speaker in the new series the name of a gem. Such as Diamond, Emerald, Ruby, Jasmine, etc.
When I win, I want my pair of M3's in piano white.