I prefer the CBR over the CSR. I find that many of the newer resorts I've stayed in have thinner walls than the older one. When I stayed at the CSR, we could hear our neighbors on either side, and footsteps of the people above us (and it didn't sound like pounding footsteps--just regular walking). I never heard a sound while in the room at the CBR.
The rooms at both were very nice. Other than the decor, there isn't much difference in the two.
I do not like the way the food court is run at the CSR. They have a host seat you, and then you go get your food. The host will get your drinks for you. They also clean the trays from your table. For this service, you are charged an extra 10% on your bill. It really adds up if you eat at the food court a lot.
If you do stay at the CBR, try to get a room close to the main pool and the food court building. We stayed in Trinidad South, and it was a good 15 minute walk from our room to the food court. We could have gotten a room in Martinique if we waited until later in the day, but the room in Trinidad South was ready so we took it. It was our worst decision of the trip.
Karen