PR has a tie in with Celebrity Cruise Lines, A friend of mine just had a series of snafus on a RT on PR to Manila and Singapore. He described the experience as ‘torture’ and would not recommend them.
He also sought out a FF program to shoot the miles earned into for credit but concluded that his flying needs would not be met.
AS in a tie up might be useful but, given the press reports and personal experience noted here, I would be highly reluctant to engage their services.