We took a group to Anse Chastanet in 2011. The resort was amazing! The customer service is over the top. We had an all meal plan and the food was incredible. They have several restaurants at the resort and instead of going to each one, we wound up in our favorite logistical location above the bar where they have live music every night. What they did for us was to bring us menus from each restaurant and we all ordered off of whichever one we wanted.
It has beautiful drift dives and the dive shop and staff is superb! We had a dedicated boat for us for the week with the same crew and with VIP service. All we had to do is take our personal non-dive stuff off the boat at the end of diving, they did all the rest! We consider Xavier, Andy and Nicholi permanent members of our dive tribe now
Bernd is the manager of the dive ops and he made our week just perfect. He said whatever you want to do, go, let me know. if anything at the resort isn't right let me know. We wanted to zip line on one day, no problem. He set it up so that they took us by boat (usually it's by bus) to the zipline; picked us up by boat with lunch and then took us off to afternoon dives. We wanted to go into town one day so he set it up to be a long surface interval instead of rushing off in the afternoon after diving. One of our surface intervals was lunch at their private beach accessible by their boat. There is a a BBQ lunch place where we could order what we wanted. We didn't leave the resort much at all because everyone loved the food and activities at the resort so can't really speak to outside activities. Anse had sailboats you could use, a beautiful beach, and snorkeling and off shore diving. They also do a Manager's Rum Punch Party at the beach restaurant for all guests on Friday that is really really nice. Bernd also arranged a private cocktail party for our group as a way of the dive shop and staff saying thank you.
The rooms are all nestled into the mountainside and are spacious, private and really nice atmosphere. I had read about issues with bugs and had brought along mosquito coils, bug spray, etc. No need to, Anse thinks of everything and the room is stocked with it. Didn't really notice many though.
We were all quite leery about the stairs before we went after reading about them (there ARE 100+ down to the dive boats) but you are not constantly running up and down them. We all agreed at the end of the week though that we were very glad about them....after the amazing food we were served for breakfast, lunch and dinner if it had not been for those stairs we would have all gained 20 pounds

Also, a little known fact it seems but there is a van that you walk inland on the path between the beach bar and the restrooms where there is a bench where a van will pick you up and deliver you to your doorstep. If it's not there in a couple of minutes, the bar staff notice and call it for you. You can also call and have it bring you down the hill.
A note about the town, Soufriere. We went there on our surface interval and Nicholi (from our boat crew) volunteered to be a guide. He walked us through the town and basically gave us a guided tour of the entire town as well as telling us the best places to buy different stuff at and then we took off in our own directions. We all found the locals to be very friendly and curious. We felt totally safe. A couple of us ladies took the water ferry from Anse back a couple of times for quick shopping trips.
Our group will definitely go back to Anse one day, it was one of the best trips that we've done!