This sax has re-inforced areas that even the AS300 (one model under the 500) doesn't have. It's built strong to hold the regulation better in control. I like the fact that if ever the bell area got dented, the sax has a clamp that can be taken off to make repair easier. The horn sounds great like a Selmer should. The high F key is handy. I like this sax so much that I am in the near future going to do a re-pad job using "roos". All keys seal nice now, but some "stick", that the roo pads would probably fix. I like the fact that there are areas between the keys with fine adjusting screws to fine tune the regulation. The adjustable thumb rest is good to have. All in all, I've a sax that performs predictably for a lot less than a Selmer Paris, and blows nice.