I was listening to the difference between my M5s and M100s this morning. The M5s carve these super sharp images in the soundscape behind them and at the same time, acoustically disappear. The images from the M100s are bolder, bigger and more dynamic and don't disappear as well acoustically unless I turn up the volume a bunch. Also as I've said before many times, the M100s sound closer to reality. It's real tough to choose between them.

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