I have the M22 v4 and they really need a sub. The M3 v4 are fairly good without a sub as long as you're not a bass loving kind of guy. Although I'd should listen to them again sans sub.
A few years ago I compare them (with sub in place). Going by memory, dangerous thing to do since I sure many of those brain cells self destructed long ago ... at first I thought that the M22's sounded slightly sibilant compared to the M3 but after comparing each to my "reference" (headphones) it was actually that the M3 bass boost was hiding a bit of the high mids. Even so, I'm splitting hairs here the M3 is a very pleasant speaker. The M22 or M3 with an EP500 is a great combo. I'd have to give the M22 a bit w/the ep.
