When we go to the Big Island we dive with Wanna-Dive in Kona. Small boat, great DM. Steve is the owner/operator and Bob is his DM/Guide.
My wife and I booked the 3 tank dives with steve for a day following the Manta-Night dive. We were the only ones booked, so we had the whole boat to ourselves. Each dive was over an hour. Bob gave us great tours and tailored the dives to us as we live on Oahu. We give this operation the 2 thumbs up. Now that the boat has been rebuilt from the frame up, so it should be alittle bit roomier on his boat.
We like the small boats though, less people, stepping on our feet.
Anyway, Good luck, let us know how it goes.