I think both are beautiful.
Typically more people will prefer the low end from the M5 as the M22 must have a sub. The M22 does play mids to highs really well just not much low end
I was drooling over the Bryston model of M5 in store for a couple years. Beautiful high end AV shop in the middle of Skid Row. For those in the know the shop is on the corner of Hastings and Carol across the street from Pigeon Park Vancouver. {Roughest neighborhood in Canada}.
Haven't yet tried the M5 my self. The 22 was my second venture into Axiom still one of my favorites. Though I now use mine as front heights/Atmos. My Anthem works them pretty hard as I run them as rear surround 7th channel reset to front on wall.{5.1.4}. They make my M80 massive entire front wall soundstage.
