The best way to listen to speakers is in your own home. From the choices on your list my preferences would be towards the Axiom M3 and Aperion 4b. Both companies have 30 day trials with Aperions being "risk-free" (no costs incurred with return freight). This would be the most cost-effective way to get a few pairs of speakers to compare in your home. Ascend Acoustics speakers are also worth consideration along side your "interested in" list which also fits inside your budget. The similarly priced models would make for a great comparison to either the Axiom or Aperion models in particular.
Instead of a centre channel I would also recommend a subwoofer to complement the mains since neither speaker has full range capabilities. I would second JohnK's subwoofer recommendation and add a centre channel or surrounds at a later date.
