That was an especially interesting read, especially with your comparison between the M50, Q40, SRH840 and the HDJ 2000.
I have the M50, HDJ 2000, have heard the Shure cans, but I have never auditioned the Q40 before.
In your review thread, your M50 was listed as somewhat bassy, even more so than the HDJ 2000. I believe you may have the bassier version of the M50 - mine is quite lacking in the low end, and even the HDJ 2000's mild bass hump still comes about as having more presence and punch. Nevertheless, it is an excellent shootout. I'm very intrigued with the Q40, which is quite highly recommended by many bassheads. Suffice to say, it is definitely not one of the more well known DJ cans out there.
Anyway, I'm still reading through your 2nd comparison thread, but so far, your comments on the cans that I've heard/owned are quite spot on (M-80, TMA-1, HDJ 2000, HD 25-1).
Btw, are you a DJ?