Was asked about my impressions now that I have lived with them for a couple months.
Regarding my observations on the M2s.... well it is tough to give a proper review at this point as I moved in November and everything changed including my system setup and most of all the room has some pretty big acoustical anomalies. I'm struggling with a midbass cancellation at the listening position. If I listen at the back of the room the sound is much fuller sounding than in the hot seat. I temporally partially fixed it by sitting a small trap on the ground (lifted 3") in front of the hot seat, but it isn't thick enough to do the whole job. I plan to hang my mondo traps from the ceiling and I think that should help. So all that said, I can judge the tonal balance from my dining room behind fairly well and I can judge things like imaging from the hot seat, but not all together quite yet.
I would say they are among the most revealing speaker I've ever heard and yet not at all harsh even on recordings that are pretty shitty. I listen to a lot of metal these days and the quality is all over the map but I can still really enjoy even the bad recordings but I definitely can hear the issues with them. I am a music first person, I don't collect music that sounds good on my stereo, I collect music I like. I have a lot of reference music and when listening to those recordings it sound a lot like live music to me. I went to about 28 concerts this year alone, so I think I can safely say I know live sound. In my guesstimate the revealing but not harsh boils down to 1) constant directivity so reflections have the same spectrum as the direct wave and 2) lack of dynamic compression which dome tweeters have in spades with dynamic music. This also means you can EQ them to your taste and it won't mess up the balance of all the interactions (you are not just EQ'ing the on axis while ignore the rest as all axis should have pretty much the same spectrum). Crown's amps have the ability to add in your own EQ to the mix and save many different presets, so you can choose a profile for the music you want to listen to if you have a hot recording.
They are capable of way more clean SPL output than I can tolerate and yet they scale as good as any speaker I've heard. By this I mean that quiet listening is every bit as lively as boisterous listening. All in all they are quite a step up from the Danley's I had before them and the Danley's were amongst the best I've owned. I was a participant somewhat recently in a blind shootout, where my Danley SM60Fs were pitted against quite a number of other offerings in the high SPL offerings from Seaton, the diy SEOS designs and something else I forgot. The Danley's were most people's favorite. However, even in that blind shootout, we had a second session (I and others were getting fatigued by this time) where the position of the speakers was changed in the lineup and it had a pretty big impact on our impressions. This reinforces my view that speakers and room are inextricably linked and equally important. Don't forget the room guys!
I pretty satisfied with the M2s. I don't see myself wanting to change them out in the next decade. Knock on wood, I know, but honestly they are so close to my own idea of what an ideal should be, I think it would be fruitless to chase the dragon any further. I think my tinkering has moved to measuring the room and playing with solutions to optimize what I got. Plus, the technical science guy in me likes measuring and studying the room more than lots of fiddly audiophile things. Of course I play around a bit with the sources, but that is more of a convenience thing. I plan to try out Roon soon.