I've never listened to Energy speakers before, but have heard good things said about them. So how big of an improvement is hard to say, but I will say that I don't think you'll be disappointed by them at all. The M60's are giant killers forsure! If you really like bass, you might consider the M80's, if that's not a big concern for you then I'd say test out the M60's forsure.
And that's the best part of Axiom, don't sweat your decision too much because if you get them and for what ever reason they fail to blow you away, then simply box them up and return them for a full refund, simple as that. I'd really love to hear a good head-to-head write-up between your Energy's and the M60's to be honest, since Energy speakers seem to be fairly popular. Which ever road you take, good luck!
