From my own listening impressions of the M3's I would not call them quite laid back. They M3's are probably less detailed and the M22's are more accurate (never have listened to the M22's). It would be a safe bet that the M3's are probably more forgiving to poorer/sibilant recordings.

I’m armed and I’m drinking. You don’t want to listen to advice from me, amigo.

-Max Payne