Both SunBreeze and Robert's Grove are good places -- and Robert's Grove is superb -- but they are somewhat different. SunBreeze is kinda motel-like whereas Robert's Grove is a full-service resort with tennis, sports equipment, roof top jacuzzis, etc. I would say it is a bit upmarket from SunBreeze.
A place similar to Robert's Grove on Ambergris would be ... well, there's nothing exactly like it, but something like Banyan Bay, a condotel, in amenities. If on the other hand you like a casual, SunBreeze-type place, then I would say Nautical Inn in Seine Bight/Placencia might be closer to SunBreeze than Robert's Grove.
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