We dove with three excellent outfits: Extended Horizons (ES), Mike Severn, and Ed Robinson. None were filled with novice divers. If I have to rank them, Ed Robinson is the best for actual dive experiences, and Extended Horizons was the best in general, but MS was very good as well. With ES, we did Cathedrals 2 and another spot. Cathedrals was amazing; wish we had done 1 as well. Diving wasn't stringent, we ascended as needed, not en mass. Our DM was a marine biologist who did an excellent, enthusiastic job of discussing species and pointing them out. ES was the best organized, sharpest operation. The boat runs on biodiesel and solar power. They have reusable water bottles. There are many places to stow gear, including hanging pouches for sunglasses (so cool). The top shaded more area that other boats. It took just three of them to run everything. The head had the most room to stand up in. They washed our gear on the return trip so that we didn't have to waste time back on land. The food was the best. They stopped for countless whale sightings, as did the other boats. A+ operation.