First, a caveat: This is a Thai boat that is marketed exclusively to Thai divers. The language is Thai, the cuisine (for the most part) is Thai, and the mode of operation is Thai.
The boat was finally completed earlier this year. It is a twin hull craft, so the beam is broader than most other dive boats. It is very stable. Almost no roll or yaw with only minor pitch. The craft is very spacious. The en suite cabins are huge with plenty of storage and closet space, standard double or twin beds and tons of power points for charging your stuff.
The upper sun deck has plenty of covered area and a hot tub (jacuzzi) big enough for about eight people.
The main deck has enough seating for everyone to dine at once. The air conditioned lounge has plenty of seating and a modern entertainment system.
The dive deck has the en suite cabins, galley, tank and gear storage and a dive lift. When I first heard about the dive lift I figured it was a useless gimmick. After using it for a few days I'm a believer. It is a very efficient way to get a whole bunch of divers in and out of the water safely and quickly. The lift is about 3X3 meters and can probably accommodate up to 12 divers. At its upper limit it is level with the dive gear area. At its lower limit it is a meter and a half under water.
One drawback of the lift is that it reduces the amount of space for gear stowage. As a result the tanks are very close together. Gearing up is a bit difficult for the first group of divers.
The dive deck doesn't have a hose or outdoor shower. As a result, the two dive deck restrooms end up being used by divers to rinse themselves and their gear. It wouldn't take much to install a couple of showers and hoses with spray nozzles leaving the bathrooms available for people who really need the toilet.
For reasons beyond me the craft has central air conditioning and central water heating. The end result is rooms that are much, much too cold and showers that are nowhere near hot enough. A fix is promised for both problems.
As is the case with many projects in Thailand, the designers of this boat seem to have forgotten that it rains now and then in Thailand. The rain runoff from the sun deck empties onto dining tables on the main deck. This would be easy to fix. I hope they do it.
During the off season Tapana Catamaran is doing weekend trips out of Chumphon to Koh Tao and vicinity. The trips are scheduled so that Bangkok based divers can leave the city after work on Thursday and get on the boat by midnight. There are four dives on Friday and Saturday and three on Sunday. Return to port is in time to get back to Bangkok by midnight Sunday. The cost of this trip is about 23,000 baht per person for the en suite cabins.
During the high season the boat will move to the Andaman side and do both north and south Andaman trips. These are four night four day trips with 14 dives. The cost is about 30,000 per person.
The Thai dive guide my wife and I had was quite good and spoke excellent English. His dive style, slow and deliberate, matches my own, so I was happy. My wife is a relatively new diver and he took several opportunities to offer her pointers and teach her a few skills. We were very pleased.
Finally, the food was especially excellent with a good range of both Thai and international dishes. One evening we had barbecued steaks (chicken, pork and beef). Another meal was a huge selection of really nice sushi. Thai dishes included som tam and larb moo, various curries, khao niao mamuang and more.
In summary, this is a really nice new boat with a few inconvenient flaws. IMHO the price is very good for a cruise of this quality.