I don't think I've ever read of anyone on this board who bought an Axiom speaker and sent it back. Well - a few cases in which they said they just upgraded higher up the Axiom chain
If you are looking at M60s and are REALLY considering them, and can't audition them in your area - I supposed you could always buy a smaller speaker, like an M22 or even M2 and return it. This might seem callous to buy a speaker even though you know you are going to return it, but I'm sure Axiom has figured this factor in a bit into their direct business model. Without a dealer network, you have to expect a certain number of "audition only" returns. Besides, I doubt highly that people ever decide against them. Their cost/performance ratio is just too damn good.
I recently heard a friend's $1100 paradigms. Not really that nice looking... sounded very good though. $700 better than my M40's? No. Better yes... I imagine that they are M60 quality (and from what I've read, similar in tone) but cost quite a bit more. I can't remember the model #, and don't feel like looking it up - but I can say that my lowly M40's did not sound bad at all compared to them, and the M60s clearly outperform them (from reviews I've read on this board).
I don't know if that last bit makes you feel better... it DOES seem like a plunge... but a plunge that most people never seem to regret.
