SOTSDO is quoted because he speaks truth.But, the real killer is the sensitivity of the keywork. Every musical instrument that I've run across prior to the EWIs is much more "analog" in its response - putting a finger onto a key doesn't instantaneous kick things up one or two octaves. In effect, the sensitivity appears to have been set by people used to electronics, but not to traditional musical instruments.
The interesting thing is that the current Yamaha WX5 isn't a 1st gen device. The WX7 and 11 came before it. There are only three "professional-grade" wind controllers still available: offerings from Yamaha, Akai, and Softwinds. And the Synthophone is prohibitively expensive -- it is built into a sax, after all (starts at a shade under $4000). Something that might be interesting would be a Lyricon II, because it (supposedly; might be "can be converted to have") has MIDI out -- i.e. you could connect it to a modern tone generator -- and a real bass clarinet mouthpiece. It's still expensive, though ($1300+), and it's the template for the Yamaha WX series. It's metal, though. You might be able to do some tweaking on the action.
UPDATE: Did some searching. It would be a CV (control voltage) to MIDI converter for the Lyricon. There are lots out there. One price I saw was $359.