The distinctive difference between a saxophone and a clarinet (or most other single-reed instruments) is that the saxophone has a conical bore that permits it to play the octave harmonic (and all harmonics above that) while a clarinet has a straight cylindrical bore that can only play the "odd harmonics" - which is why the clarinet fingering is set up to play an octave and a half with one sequence of fingerings and "breaks" in the middle of the octave to continue upward repeating essentially the same fingerings.

Some double-reed instruments behave as "open at both ends" and can play the octave harmonic, which is one characteristic that distinguishes an oboe from a clarinet.

It probably would be less rudely offensive to Adolphe Sax to call the Xaphoon a bamboo clarinet, and a decent saxophonist would feel rather limited without having the full four octave range (or at least the bottom three) of a "real sax" available; although as "something to toy with" there's nothing wrong with adapting anything that makes pleasant(?) noises to a musical novelty act.

A disadvantage of playing with an odd instrument is that it may be difficult to find anyone to play with, although that can also be an advantage since there's unlikely to be anyone handy for others to compare you with. (You can enjoy it at your own pace.) An ambitious experimenter would of course want to try to organize at least a trio to include some harmony. ... perhaps(?).

I'm having a little difficulty visualizing a Xaphoon orchestra, but ... .

John