First of all, if you're looking for a way to play the sax or any instrument with similar keying, I don't think anything comes even close. The keys are laid out perfectly, the expression sensor works great and the instinct to adjust your mouth on the mouthpiece as you would with a real sax makes the experience very immersive. It is great fun and if the alternative is "not playing because it would be too loud", well, what are we talking about then?
What could and should be better? Well, at very very low wind pressures, the sound is not perfect but keeps wondering whether it should or shouldn't play the note. I'm talking about the lowest threshold here, it doesn't represent a big issue but once you notice that, above all with headphones, it's a bit present.
Second, preamp for line-out is a bit weak. Perfect for headphones, but when plugged to an active portable speaker, max volume of both devices (sax + speaker) yields a non impressive sound power.
The keys are digital. It's great that they show you immediately all your imperfections, but playing the sax is an analog experience and a 95% pressed key in a real sax still plays the right note, while on this one it doesn't. For fast transitions you'd better be a hell of a player.
Other improvements relate to the midi functionality, a little primitive, and the bluetooth, which doesn't allow inbound connections, which are limited to line-in.
So, it doesn't get better than this in the market, I believe, I would buy it over and over again, but I still wish to see some improvements.
