First of all a few words on Ko Lanta, the island that Costa Lanta is located, it is situated in the wider Krabi area, south of Phi Phi island. Despite the fact that nature and the beaches are quite similar, the island atmosphere is more laid back without the excesses of Phi Phi, Krabi and Phuket.
The hotel itself is on the north part of the island at the end of a long stretch of beach. It really stands out from the rest of the hotels on the island because the architectural style of the whole hotel is more modern/designer than thai.
The whole design of the bungalows is really different and innovative, with the roof of the bungalow consisting of hardened plastic slabs, so you had direct contact with nature. This hotel is not for people who are afraid of creepy crawlies, since you will see all sorts of things wandering in the bathroom (we went in the rainy season), all were harmless, but I suppose those not accustomed to them, could be a bit worried.

This is one of the most interesting hotels we have stayed in and I highly recommend it to people who want something out of the ordinary.
Service was good, but not something to write home about. Since most of the clients were European (as most of the tourists in Ko Lanta), the service was more "European" than "American" style.

The cuisine is probably the best on the island, and also very good value compared to the cheaper but crappier alternatives on the main village.
The cocktails at the bar are also good.
I would recommend that you do not book excursions via the hote, just wander to the tourist agencies down the beach that are offering the same trips 20% cheaper.

Overall a good choice in a beautiful island

Costa Lanta hotel concept is great, pictures on the net are nice but when my wife and I got there, how bad was the surprise.

This hotel has not been maintained since the opening. It was not only the garden that was abandoned or the pool but everything was dirty, not maintained, chairs at the bar were dusty…., we had the feeling that this resort is close to go bankrupt, that the hotel has not either enough people to maintain it or a very poor management.

We paid €100 per night (low season) for something that even doesn't worth the half. On top of this, most of the hotel personal (waiters) is far from being friendly which is unusual in Thailand. I am not mentioning their level of English. We stayed 1 night instead of 5 as initially planned.

stayed here 4 days 3 nights over Easter, food here is EXCELLENT! was here with 4 friends, we tried other places on the beach as well as in town but the food here was very good

service is slow coz there's only 1 person cooking in the kitchen and only 1-2 staff manning the bar/restaurant/pool but if you're on vacation, it shouldn't be a big deal

the rooms were small but interesting/unique, some would consider the design strange, decide for yourself on this one

the semi opened bathroom = lots of bugs so if you can't stand bugs, this would not be the place for you

we checked out Rayavadee before coming here, for 1/3 of the price, you get excellent food, decent service, a pool/beach almost all to yourself, decent room/bed, great sunsets and moonsets (at 5 in the morning)

girlfriend's husband was able to find clams on the beach, rinse and eat them raw!

we took a boat out and went snorkeling and island hopping. This place was not as beautiful as ie Maldives or Bora Bora, but even for my friends that flew over from SF just for 3 nights, we all thought it was worth it

Totally agree with the traveller from Australia . Costa Lanta is a very unique and relaxing place to begin your holiday in Thailand (it was my first stop as a honeymooner). My main complaint is that in our sea-view standard room, the space for the bedroom wasn’t much so we couldn’t really spent a lot of time in the room (there is no tv also). On the other hand, when you go to Thailand, you don’t really want to spent your hours in a room, do you?
I would recommend this resort for a 3-4 day stay.