It depends on what you're looking for. I happen to love love love Faena! 1 Hotel is also a good choice. Setai is another favorite of mine. I tend to not really like the W but that's a matter of personal preference, I also stay clear of Fontainebleau, though I'll admit if you're looking for nightlife, a good stretch of beach and close enough to the action Fontainebleau certainly suffices for most.
My first choice would be Faena though I find the staff, gracious and really up to standard, our butler went above and beyond. Do go to Pao although, know that the later you make your reservation for the crowd changes...from interesting to downright weird. Beware, its loud....like very loud. I honestly thought there wasn't a restaurant louder than cafe abbracci, but Pao has them beat. But its good people watching and delightful food.
The Setai is also good although I put it a tiny notch below Faena because at times the service in the restaurant can be hit and miss. But undoubtedly the spa at the Setai has the spa at the Faena beat....how they don't have someone that does manicures and pedicures at a spa is beyond me, they'll send you next door to the Miami Edition. I think the beach in front of both is equally nice. The Setai is a tad bit south and closer to South Beach proper but not by a significant amount.