Stopped here for lunch and dinner during recent vacation. Atmosphere is pretty laid back - comfortable setting, often live music playing, nice layout. Staff is friendly and welcoming. Food is terrific, drinks can run on the "creative" side. As other reviews suggest - it's bigger inside than it appears. Please note: it sometimes gets busy and service slows down a bit (at least it was at dinner) as staff is attentive to customers (also see: Island Time). Like many other restaurants on the Island, it can get a bit pricey, however portion sizes are good. One of us ordered the 12 oz prime rib and ended up with something closer to 14 or a pound (we actually had to confirm they didn't goof up and charge us for the 24 oz).
I noticed an earlier review expressing frustration over a lack of gluten-free options. To be fair to Keoki's, the menu makes it clear that certain items may not be made with ingredients containing gluten, however it's possible they could be exposed to gluten due to the nature of their kitchen. If you are extremely sensitive to gluten, do your research ahead of time. Look up the menu. If you're unclear on something, call them ahead of time and check. They genuinely seem to care about getting things right and will answer your questions.
If you don't mind a little slowness during the evening (more time to take in the atmosphere), I'd highly recommend this place.