Pono Mango owner here...
I'm with Deach. Although I do like the sound of mine, it has been a struggle to get it where I want it.
Check out most of my later vids (in my sig) for sound samples and low G tuning.
It's pretty, and I do love mine now, but I will not buy another Pono.
That said, the mango is a surprisingly good tone wood - my issues are with Pono construction, not the wood.
HoosierHiver is waiting for some Mango prototypes for his Mainland line... I'm looking forward to hearing those. Hard to go wrong with Mainland (yes, I'm biased... Hoosier is da bomb). Maybe he can shed some light on those for us.
For the record... my next uke is very likely a koaloha unless I just bite the bullet and get a custom.