I dive a lot, and have been fortunate to have been spoiled with some fantastic scuba adventures in many places around the world. Remembering my first few dives, I understand the excellent ratings given here by a lot of new divers, with their enthusiasm reflected in their bubbly reports. I was just as excited starting out myself, even in the ice cold waters of Canada wrestling with 12 mm wetsuits, lobster gloves, and 30kg weight belts.
When you go to a diving destination and rely on a dive shop, you know you can't expect all that much when you use rental gear. However, it would be nice to have a BC that actually inflated from the tank other than manually by mouth while underwater, tank connections that didn't leak, a depth gauge that wasn't broken, tank fasteners on the BC that actually held the tank from floating away free, fins that fit, a wetsuit that wasn't old and worn out, and weight belts that had buckles that weren't so worn out they didn't come constantly loose slipping to your knees. 30 years of dive experience helped me deal with these issues without panic, but perhaps it won't go as well for a new diver when it happens to them 25m underwater.
After surfacing from a second dive and long underwater swim, we could not see our boat anywhere. We floated on the surface until eventually, we saw our dive boat anchored far away on the horizon, behind another dive boat. On deck, nobody was looking out for us to reposition the pickup closer, so we all had to do a marathon surface swim for our pickup for about 20 minutes, eventually giving me leg cramps, which made me cancel any more diving for that day, and my plans for a night dive.
Once on board, the dive boat had almost no fresh water to rinse yourself off, or your gear with. Either they ran out, didn't have any, or the pump failed. I used some bottled water.
In mid February, although the sea was calm, the water visibility was still poor being only about 7m with a lot of water borne sediment and plankton. Apparently, it should clear up nicely in the spring and summertime.
I had come to Ko Tau and planned to do a week of diving, but after 1 day of gear issues, boat issues, and poor visibility, I realized this wasn't about to change, and had enough and decided to head back to the mainland for other Thai adventures and hopped on the ferry the next day.
At the time, Big Blue was starting the process of moving to their new facility from the old place as the lease was up, so I hope they have taken the opportunity to leave the old worn out gear behind, repair some boat equipment and retrain some skippers, and start fresh.
I thought the divemasters there were awesome, considering what they had to work with.
There seems to be about a hundred dive shops on Ko Tau that teach courses, and take you out diving, so my advice would be don't commit to just one place, just get there, and look around for a good shop with gear you feel comfortable with, for a reasonable price. Most have half price accommodation deals if you dive.