Nakhon Si Thammarat - Quite literally, the friendliest place I have ever been in my life. This island may be the highlight of my trip so far. When they said Thailand is the "Land of Smiles," I was a bit disappointed. I mean, everywhere I've gone so far has been somewhat friendly, but the Land of Smiles? Let me paint a picture of Thammarat. Everyone that passed by us, waved. We were constantly honked at by passing cars. Young children giggled as we walked by. Unlike in Bangkok (where people usually just stare at you), people would actively smile and say hi to you. Lisa and I were invited into a random person's house and given cake. From what I hear, we stayed in the friendliest area of the island (Khanom). Additionally, there were very few to no tourists there, giving the island a small-town, personal feel. If you're looking for a chilled-out, relaxing time, I cannot recommend it enough.
Ko Pha Ngan - OK. The only reason we went to this island was to attend a Full Moon party. I really can't comment on the island itself, as I was there less than one day. Full Moon party was alright, nothing to write home about. In all honesty, this island sucked more money out of us in one day than I'm OK with.
Ko Samui - Without exaggerating, this island is the most touristy place I've been in Thailand - even more than Bangkok. The beach was very nice, but prices were generally expensive, and everywhere was very crowded. I haven't been to Phuket, but I'd imagine the level of tourism is similar. If you're into bars and clubs and expensive accommodation, this island is for you. If not, I'd recommend finding a more relaxing place.
The South of Thailand has many nice places to offer. However, it is by far the most expensive area I've been in the country. Unless you are traveling with a lot of money, I'd recommend skipping most of the hotspots. Perhaps go to one or two lesser known islands, or just skip it entirely. Look to spend approximately twice as much in the South as elsewhere. Transportation and accommodation are not cheap.
On another note, I said farewell to Lisa yesterday. She is traveling back to South Africa, and will be missed.
Up next: Cambodia, which I leave for in two days!