Check out the M80 and M80HP drivers. The HP version using the same drivers as the M100. I think the HP option is, to be frank, a waste of money, and that's why I bought V4 non-HP M80's. But....there have been others on this site who said the HP version sounded better to them. I can't help but think that is psychological, and not real. Oh wait, forget it…..I don’t want to know, cause then I’d just buy other friggin set of speakers if they do sound better….
As far as sub with stereo goes, I use an EP600 with M80’s (TI models). I have it crossed at 40. I love it. The system sound naked without it.