I think the reed it comes with is too heavy (a 2.5). I replaced with a 1.5 and got some improvement, but the mouth piece seems a little thick and the bore too short. It is very difficult to play on pitch. I have no doubt, with a lot of practice, I could get better, but I think it much too difficult to master for most people and frankly, it is not very pleasing to the ear.
I have a Duduk which is about 4 - 6 longer with a smaller diameter bore and it plays bang on pitch with a whole lot less effort. It cost just over $120.00, so it's nearly double the price, but it has the advantage of having an alto mouth piece adapter so you don't have to play with the traditional double reed if you don't want to. It is made of almond wood and has much fuller, sweeter and mellow sound, more like a sax.
There are some bamboo saxophones out there not much larger in size which sound much better and have the benefit of a traditional "beaked" mouthpiece. I frankly do not understand the 5 star reviews for the Xaphoon. Perhaps they are for the bamboo version. A small portable instrument is nice to have for travel, but it still has to have a pleasing sound. I'm afraid the plastic Xaphoon doesn't give the tone I'm looking for.

I've played low clarinets (alto, bass, countrabass) for years, and also some alto- and tenor sax, so I thought it would be fun to have a simple, pocket-sized, easy-to-play reed instrument handy.

Well, it would be -- but this ain't it.

It is "pocket-sized", sort of, so I'll give it that.

It's anything but easy-to-play, though. The chief problem, IMO, is the oddly-shaped mouthpiece. I'm not sure what possessed them to put such a thick, rounded mouthpiece on this, rather than something with more of a "beak", like a standard clarinet or sax mouthpiece. It feels awkward in the mouth, and is difficult to hold in proper playing position with your teeth. The large mouthpiece forces your mouth open further than it should be for such a small instrument, which makes you waste a lot of air to support the sound.

One thing you may want to do is put a more flexible reed on the xaphoon. It comes with a 2-1/2, but 2, or even 1-1/2 will make it much easier to blow, although the tone will suffer somewhat.

As to fingering, I used to think that bagpipe chanters and bassoons had strange fingering patterns, but the xaphoon is out to give them some competition. Yes, this has a fully chromatic range of about two octaves -- once you learn all the arcane cross-fingerings for the accidentals. As another reviewer pointed out, there's a reason why saxophones have all those keys.

Finally, the sound is rough and raucous. Not necessarily a bad thing, but if you're expecting to sound like Paul Desmond, well, save up and buy an alto sax. I find the sound more reminiscent of a Renaissance racket or crumhorn, than of a sax or clarinet. Think of the nasal "brraap!" of a goose in distress. I have to wonder if this sound was intentional on the part of the designer, because a few simple changes would, I believe, mellow out the sound considerably: a thinner, more beaked mouthpiece, for instance, with a narrower channel that took a clarinet reed, instead of a sax read. This would probably also make the instrument easier to blow, as well.

You can, of course, find youtube videos which demonstrate this instrument being played with some considerable facility and tone. I know from experience that one can become virtuostic on pretty much any instrument, no matter how primitive, given sufficient time, dedication, and practice. And that's what you will need to become an accomplished xaphoon player: dedication, time, and a lot of practice. Only you can decide if it is worth investing that level of effort in this relative oddity, as opposed to spending it studying clarinet, saxophone, or some other more conventional orchestral instrument.

For me, it failed to fulfill my immediate expectations. For $20-$30 I would have probably just shrugged it off. But for $70, I feel sort of obligated to put in some time, so I probably will eventually reach some level of accomplishment on the instrument. Not, however, an instrument I'd recommend to beginners. If you're willing to make some serious effort, by all means go for the xaphoon. But if what you really want is to feel good about being able to dash off "Hot Cross Buns" with a sweet tone, in a week or two, buy a $15 recorder, instead.

Still have to practice to learn the accidental notes, but it sounds great and is a lot of fun in a small package. I play clarinet, so learning this embouchure took some time, but was not difficult.

I have to make myself stop practicing this! I am having so much fun, I want to practice at every possible moment! I play other instruments, but this is my first attempt at a reed instrument, and it was not love at first sight! The first 2 days, I really wondered if I had made a mistake buying it. But on the 3rd day, something magical happened, and the notes that were recognizable began to outnumber the honks and squawks. It will probably take me another 2-3 months to be at an acceptable performance level (my audiences are very forgiving), but they are going to love the full and expressive sound that this little instrument delivers. I truly enjoy this little guy, and I look forward to playing it publicly. And if anyone needs a carry case for it, Ali Express sells one made specifically for the xaphoon. (Also, I emailed the guy who invented/sells this (twice, actually), and I was pleasantly surprised when he responded both times, including with a tip on staying in tune!

I am so totally in love with this! Easy to play once you figure out the embouchure differences from other reed instruments. Absolutely love the sound. It is not a thin sound like a recorder, but a very full sound that is both saxy and clarinetty. If you are considering it, I'd recommend jumping in and doing it. Just make sure to get the Maui brand; it is the original and best. Love the fact that it is light weight, portable, and very sturdy. It is a lot of fun to take along places to play, and not to have to worry about damage to your instrument. (i.e. sand in your pads, or the weather being to hot or cold for your wood clarinet) This is easily my favorite purchase in a long time. I watched a review video by Jeremy Katz music prior to purchase, if you haven't heard the sound of one of these that is a great place to start.