Big Blue Diving is exactly what they say they are, plus the friendliest, most helpful staff. I did one of their online packages to get my Advanced Open Water + 10 fun dives, and it was the best value diving I've ever done or even heard of for the amateur diver. The on-site hostel is pleasant, the dive masters are all great leaders, the instructors really know their stuff. The restaurant has good food (tho a little pricey), the dive boats are nice and comfortable for the half day trips they do multiple times each day. I dove with 6 different dive masters and instructors in my 15 dives, and they were all super. I recommend Big Blue to everyone who goes to Thailand, whether they were planning on going diving or not!