I give the courses a 5 and the accommodation a 3 (...

I give the courses a 5 and the accommodation a 3 (hence the 4). I took Advanced Open Water and stuck around to do some fun dives. Big Rich was my instructor and I felt that I was in good hands. The culture of Crystal is kind of a big family, with mostly expats from all over the world. This is one of the bigger dive centers on Koh Tao and there are lots of people hanging out together before and after diving. You meet in the bar area before you head to get your gear, and then hang out at the bar when you get back. The location is really convenient because it's walkable from the ferry and walkable to food in Mae Haad. It also means that loading to the dive boats is super easy (walking to that same ferry dock) in comparison to the dive centers on Sairee beach. If you're traveling solo, having a dive center with a social feel is great. You are diving on boats with up to 20+ other divers, but you're always with a small group per Dive Master, so you know you've got a good ratio and an experienced person keeping an eye on you even for fun dives. On the accommodation, a fan room is included with the course, which is great and makes it convenient and a good deal. I had bungalow A1 which has an amazing view right on the beach. But you need to know the room is BASIC. The only furniture is a bed and a chair. You need to know that going in. There is also a fan, which in my bungalow was kind of weak. The windows in A1 don't all have screens so if it's a hot day you end up debating mosquitos (all windows open) or high heat (with some windows closed). The bathrooms don't come with toilet paper (Thai people use the little hose thing), so you have to be ready to do that or buy some. The shower is part of the bathroom and unfortunately the location of the drain in A1 meant that water gathered on the floor and didn't drain out well. That said, I still enjoyed my stay at Crystal and would recommend it. I met some cool people, upped my scuba skills and got to see a whale shark!!