Decision is always irrational.
Subjective. Compare with buying property (your home).
Ok.
I personally like them both
including Kanilea K-1 based models (K-2, K-3, K-4, and etc.), KPE, KCS.
I personally like more Ebony (and my brain already programmed since childhood that Ebony is as strong as millions-years-old sap).
I personally prefer some dark-reddish patterns which is Kanilea Deluxe. Kanilea chooses yellowish-golden for their premium ukuleles.
And now,
objective. Unproven theoretical, and very logical.
- Ebony is stronger than Rosewood
- Ebony will change shape much less over time, humidity changes have less impact on Ebony
- Ebony will better transfer frequencies. Rosewood, which is softer, may dump some frequencies.
- Ebony will hold frets much stronger than Rosewood.
- Bone saddle (of Kiwaya) is super good but there is no guarantee for consistent density.
- Saddle arguments itself do not have good reasoning except that some may get better fit in the bridge and we may mistakenly say "bone is better than plastic" when real reason is better fit. Also, whi knows why we have break-in time for Koa? Maybe it is saddle & bridge fit which becomes better over time? Some in this forum suggest to place your Kanilea in front of speakers and put non-stop Hawaiian music LOL
We are messing with real reason and consequences here. Yes wood sounds better over time, but some reported amazing change in sound quality just within a week: it cannot be aged wood!
- Some reported changing strings (from X to Y) improves sound. I myself reported for example intonation problems with factory provided Aquila strings and how it disappeared when I changed strings to Oasis. But... have you tried to change from X to X (from the same vendor!)? Have you tried to avoid explicit stretching (with your fingers) when you set new strings? Or to change the way you set new strings?
Also... our hearing is different; and hearing of the audience from 5-10 feet away is not the same as our hearing from 1 foot. And so on.
Anyway, Kanile'a is
the winner.
So many rationale here. Including lifetime warranty, uniqueness, 14 frets to body (instead of 12) which is really "playability" characteristic.
Ebony fretboard which means we can setup it much better that rosewood fretboard. For example, some kind of steel can be sharpened much better than some other kinds, and will hold sharpness longer. Same here. You can reach better results with Ebony & X-frets than with Rosewood & Y-frets.
But... "The Jury Is Still Out"
I personally prefer Kanile'a Super Soprano (ebony slotted fretboard, TUSQ, silk for neck & gloss for body), I believe Kanile'a gives much much more value in the same price range; but I'd love to own someday Kiwaya KTS-4 just for fun with 12 frets and 260 gram weight!!!