Bear in mind, the M22 came out after the other speakers in the Axiom lineup (except the most recent M2i). The M3 was pretty much the reigning champion of bookshelf speakers prior to that time. In that context, the evolution of the lineup of towers, from M40 to M80, makes complete sense.

Don't discount the M40 and M50...they sound great, and depending on your room, budget, aesthetic and musical tastes, could very well be a better buy than the M22.