I have HPM 100's in one room and M60's in another. I go back in forth between the rooms and can never decide which I like better. The bass is definately lower with the HPM's but the sub in the room with M60's fills the gap plus more lows. As for mids and highs they are very similar.
The HPM's do not reach very low when I connect them to my Denon AVR 4308ci, when they are connected to the Sansui 8080 they have really good lows and I really haven't tried the M60's with the Sansui so maybe they would compete better with the lows of the HPM100's. I don't regret the purchase of either of the those speakers.
