I've trained a lot all over Thailand (Phuket, Chiang Mai, Bangkok) so I can offer a bit of input.
Training jiu jitsu in Thailand basically sucks. Unlike regular gyms where the trainer has an incentive to slowly grow his gym over a long period of time and cultivate a good environment, what I call "traveller gyms" are just the opposite. A large number of the people who show up have never trained before and the trainers are hired employees just there to work a job and live in a nice place. People usually stay for a few weeks at the most so it's hard to get to know anyone really worth training with (non-spastic, skilled, friendly). There's a lot of white-belt fever (guys who really need to "win") and the trainers don't put much effort in unless you already have a higher belt level or maybe try hard to buddy up. Roger Huerta (who is awesome) is the clearest exception to that but I don't think he teaches much. The good trainers tend to be Brazilian and likewise trend toward the gi; although the climate and increasing overall interest leans toward no-gi. I really want to like training in Thailand (having spent around five years there) but it is invariably disappointing. Anyway, there's plenty of freedom to work whatever game you want because nobody cares.
Training in Thailand is about the whole package, I guess; if you're into doing Muay Thai, Cross-fit, being in Asia, augering into the training lifestyle etc.
I don't know if this is your first trip or not but:
1. Don't stay at the gyms. (costly, noisy, smelly)
2. Don't stay, and avoid eating, on the road the gyms are on. (costly, food isn't the best)
3. Get a motorbike and find a place within 5 or 10 minutes, toward the hills is best.
4. Cooking can save you a lot of money. If you can't find a place where you can cook, bring/buy a camp stove and hit up the Villa Market and local markets for produce.
5. If you're staying for any amount of time, it really benefits you to try and learn 50-100 words of Thai. Memrise.com is an excellent resource for that.
Happy training.