Cocos is scalloped hammerhead central. If you want to get close to hammerheads daily, and see a wall of hammerhead sharks, there are not many places that can compare than Cocos. Expect to also see massive schools of Jacks, lots of marbled rays, Galapagos sharks, silvertip sharks, silky sharks and white tip reef sharks. Making an occasional appearance are also tiger sharks, whale sharks and mantas. leave your macro lens at home. The best night dive in the world can also be found in Cocos where you see hundreds of whitetips hunting for food and getting into a feeding frenzy. There is no need for baited shark dives. The island itself is a beauty. You will pass by numerous waterfalls on your way to the dive sites. A visit to to the ranger station and a hike up to a viewpoint is also a must do on Cocos Island.
A dive trip to Cocos is an adventure of a lifetime and well worth the 36 hour crossing from Puntarenas on mainland Costa Rica.

Fish n Fins is the first dive center to open in Palau. The current owners, Tova and Navot are very respected divers in the Palau diving community. They have a great crew of captains, divemasters and office staff that will take care of your every need. Their dive center is located minutes from downtown Koror and many of the top resorts that divers stay at. There is also a muck dive right at their dive center dock where there are mating mandarinfish. Just ask them and they will hand you a tank and show you where to go.
They have boat sizes for all groups, from smaller speed boats to luxury liveaboards, the Ocean Hunter II. The dive shop is stocked with everything you need including reef hooks. There are large rinse tanks for all your gear, including camera gear. As a bonus, they have a bar/restaurant where you can grab a beer and some local snacks when your boat returns after an awesome day of diving.

Palau Royal is a great value option in Palau. It is a large hotel with tennis courts, pool and even their own private beach. The rooms are simple but clean and well decorated, and they all have a balcony. Some balconies face the garden/pond/marina and some face the beach/sea. The breakfast restaurant is large and has good asian and western breakfast options. I didn't have lunch/dinner in the hotel. A famous Palau restaurant called Carp is about a 5 minute walk from the hotel. There is a bar in the restaurant and a poolside bar too. Downtown Koror is about a 5-10min taxi ride away and the front desk will call a taxi.
There is no shore diving, but there are wrecks within a short 5-10 min boat ride from the resort and some of the more famous dive sites like Blue Corner and German Channel are about 30 mins from the resort.

The Junk is a very cool boat with a very interesting history including being used in a James Bond film. The cabins are adequate and there are plenty of places on the boat to hang out. The boat is well maintained and didn't have any issues with leaking cabins or broken toilets on my 10 day trip. Food is plentiful and good with a mix of excellent Thai food and some western cuisine. The crew were excellent and a lot of fun, and they brought us to a few beaches to hang out.
One of the coolest things about The Junk is that you get to help raise the sails in the old school way on the last day and go sailing.
Schedules and itineraries vary and they do go to some of the best dive sites in Thailand like Hin Daeng and Hin Muang and Richelieu Rock.