I would have to weigh more on the side of a singles hang out instead of couples.
I agree couples can have a great time there! But - if you have a significant other who is even a little bit jealous it could be a long trip. There are alot of hot bodies - girls and guys - and everyone is so friendly. In the pools, at the bars and just everywhere. This is not the place to try and keep him/her on a short leash.
I watched a couple we took with us last year really struggle with this and it was a lessoned learned.