I don't have M5OW. I have M2OW in 2-channel spaced 11.5 ft apart and I sit 12.5 ft away. They are in 2.2 channel.

The centers of the tweeters are 3" below my ears. I decided on this height through extensive experimentation in my room. With this height, the images appear at the height I would expect with broad and deep soundstage. With the tweeters at ear height, the images appeared too high up. I noticed no difference in frequency response/brightness/dullness at the two different heights.

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