The Q looks to be an effort for Leica to appeal to non-RF shooters who might come from DSLR or other Mirrorless offerings, but it doesn't interest me much. To be honest, I was tempted at first, too. I immediately thought that this would be a great backup to my M9 when the lights are low, but then I realized the flaw in that line of thinking... it will only be an second option for me. What I wanted was a camera that's good enough to replace the M9 to be my first option.
Since I shot exclusively with the 28'Cron on Sunday in the San Diego County Fair, I thought about how it would have been if I had the Q instead? I think it would have been just fine. For the shots of my son on the rides, I would have relied on the autofocus and it probably would have gotten me more shots than I did with the RF-and-wait method. It could also miss a few, like the shot above. It wasn't mission critical for me to get every shot in the right focus, but I got enough keepers to make me and my family happy, and most importantly, I thoroughly enjoyed the photo-taking process because I was 100% involved. If I had shot with the Q instead, I feel my own efforts or involvement would be greatly reduced to the level of using it as a point-and-shoot. Obviously, that's not where I want to be.
I know one can turn off all the auto-ness and shoot manual, but focus-by-wire with focus-peaking and live view zoom doesn't appeal to me. So... for now, I'll keep waiting. I'll wait for the right M9 replacement, while enjoy every minute with the M9.