Two years ago was my first Axpona (first audio show ever actually). Was lucky enough to go early on the first day so it wasn't that crowded. I had a great time. Was able to check out so many new products. Really couldn't believe how many companies are out there that I had never heard of!
As many have stated, don't go there expecting to hear everything at it's best. But, I think you can get a good idea of what a speaker might sound like in your room. I was blown away by the sound in a few rooms though - Vinni Rossi, Maggie LRS, Sanders, DeVore, just to name a few. Ended up buying the LRS shortly thereafter.
Totally worth a trip IMO. Even just to go once. I am looking forward to going again in April.