My wife and I have stayed at Gumbo Limbo twice in the last year. We stayed for ten days in June and then returned for Christmas/New Years 2010 for another ten-day visit. Both times we stayed in Villa Indio. I highly recommend either of the villas, although we prefer Vill Indio due to the fact that you have a private pool outside your front deck.
The views are amazing and the staff is awesome. Sonny is the man! His partner Mikaeli (sp?) is a great Italian guy who's dinners at the on-site restaurant are not to be missed. He even gave me an impromptu Spanish lesson for two hours over lunch one day!
I haven't stayed at Marbella, but I can't recommend Gumbo Limbo highly enough. Have a great vacation wherever you stay and...Pura Vida!!!
Edited: 8:19 pm, April 07, 2010