I haven't stayed at Rockys but have booked it for my wedding next summer. My best friend stayed there in January and loved it. The rooms were beautiful (especially the beachfront rooms) and the service was excellent.
The beaches are quite small I think (small coves rather than acres of white sand) with large rocks - in January Claire found she could swim easily from the beach but I am not sure what the tides will be like in September. However, and this was a big plus for me, the beaches are private.
A recent posting on Rocky's own website says that it is not a five minute stumble from Lamai but it is a five minute drive.
As I said, I haven't stayed there yet but the level of service that I have received from them regarding the wedding planning has been excellent to date.