Nemo near south beach was great. My only complaint was that we had to wait for 45 minutes even though we had reservations. But, the beef salad appetizer was delicious and the short ribs as well. I went to Shoji for drinks first and enjoyed the lychee martini.
I also spent one night in Coconut Grove at Las Culebrinas based on board reccs. I didn't enjoy the meal at all. The steak was not flavorful and was served with soggy over-dressed salad and boiled potatoes.
Another night I was in Fort Lauderdale at Las Olas and had dinner at Max's Cafe based on a friend's tip that it was an inexpensive gem. It was not. The entree was tiny and about the level of cafeteria cooking. The waiters were slow and also had to bus the tables. It is inexpensive, $6.99 for entrees, but not worth going.
Hope others have more success down south :)