Anectodal (i.e. talking out my a$$) - I recall reading credible comparisons that the Aperion bookshelf speakers presented a somewhat more laid-back sonic signature than the Axioms. You may very well find that sound preferable. Only your ears can decide.
As for me, I love the M60's. They are consistently exciting and rewarding to experience. I have no remorse whatsoever.
The earlier comments about sub proficiency are worth repeating; not all subs are created equal. Likewise, a true three-way speaker (like the M60) PLUS a a good sub will give you more placement options and likely higher performance than a pair of two-ways sitting on top of sub modules.
