20 years ago I got my first bamboo Mini Pocket Sax; it had a warmer timbre than the current injection-mold pocket sax, but it was pitched a wee bit sharp, making it difficult to play with other musicians.
The current pocket sax is pitched more consistently (not being hand-made, as the bamboo Mini Pocket Sax was). Since tenor sax is my favorite horn, it is nice that such a small horn uses such a big, familiar, fairly easy-to-control tenor reed.
The ligature & reed that come with the horn are OK, but one may benefit from exploring different ligatures & reed-strengths. As some reviews have stated, the 2nd register is more difficult to control, pitch-wise, but there is an octave + a fourth of effective low-register range (that 'in-between-registers' sharp 11th requires embouchure tricks to blow correctly).
And, yes, the fingering is tough to master at first (any holes not completely closed will sink the ship), plus it seems best in the key of 'F' due to the 'Bb vs. B' fingering, but that is quite similar to the the manner in which East Indian 'bansuri' flutes are named in terms of tonic pitch. Or you could call it 'C mixolydian,' with an easy to hit flatted 7th.
But you do get 2 octaves, low C through mid C to high C, if you can adjust your embouchure enough for accurate pitch, especially as more holes are open (pocket sax creator Brian Wittman's 'Jungle Jazz' CD has some 'pitchy' moments too, while being a nice listen). And some semitones require 'half-holing,' sometimes less accurate at faster tempos, but there are easy enough alternate fingerings for most of them.
This horn is in my pocket every day at work. Over-worked employees often request songs, which I am happy to oblige, given such a versatile instrument. And it has been likened to the Armenian 'duduk' from some 'in-the-know' listeners, given the mellow tone I have found through reed/ligature/embouchure adjustments.
Work with it, and you may find that 'sweet spot' that works for you. A few moments of music each day is good medicine for the soul.
I play this horn every day! I love it.