It's been some time since I listened to M5s. I'm at my friend's, listening to them through my almost 20 year-old Denon 2105. It sounds to me like the highs on the M5 are more clear, airy and have a longer sustain than the actives. They sound more satisfying. I think I'll have to do a careful compare at my place.

House of the Rising Sone
Out in the mid or far field
Dedicated mid-woofers are over-rated