Unfortunately, KoAloha does not disclose what kind of Acacia they are using. Pono, on the other hand states they are using "acacia preta", otherwise known as "monkeypod" or "vietnamese koa" or in english "rain tree", which is a recognized tonewood (though not from the acacia family of plants). In contrast, Kala is using "acacia confusa", which is an invasive weed the marketers call "taiwanese koa". But whatever the Acacia they use for the Opios, they sound quite nice.- The pineapple model from Pono is made from Mango wood, whereas the Opio is Acacia which is a close relative to Hawaiian Koa.
Your selection shows that you did your homework: both brands will give you the best value I have come across on the ukulele market: Both are solid wood and build in Asia to the specs of Hawaiian companies who know what they are doing (instead of guitar companies who just add a little inexpensive toy to their line-up). I have owned several of each brand and would say that you can't go wrong with either one of them. Still, there are some interesting differences that you might already be aware of:
- Pono has geared tuners, whereas the sopranos and concerts from KoAloha have friction tuners. Many people like them, but they are harder to fine-tune than geared tuners.
- Pono uses a perfectly flat satin finish on their basic models and a glass-like gloss finish on their deluxe and pro classic models. The finish from KoAloha Opio, on the other hand, is kind of a semi-gloss with some open pores and dimples. To me, this is the one thing where they could and should improve.
- The pineapple model from Pono is made from Mango wood, whereas the Opio is Acacia which is a close relative to Hawaiian Koa.
My personal assessment is that overall, Pono offers a better value (cleaner built & nicer finish for a lower price), but Opio might have the edge in terms of sound.