I never go a restaurant for stone crab. I always pick up jumbo or collosal claws at Publix supermarket or at Carmine's Market (I think there is one in Aventura still). They are always fresh [NEVER BUY FROZEN STONE CRAB]. They'll crack the claws on request and pack them on ice, and they sell the mustard sauce (or you can make your own, it's pretty simple). Just take home or to a picnic spot, and enjoy with a sav. blanc or champagne.
It's like buying wine in a restaurant: you are spending 2 to 3 times as much for the exact same product. So save your money, or buy three times as much stone crab as you'd get in a restaurant, and have a feast.
Charley's Crab in Palm Beach is part of the Landry's Seafood chain these days. It used to be owned by Chuck Muer, but was sold (along with Chuck and Harold's and the rest of the Muer restaurants) after Chuck and 3 others vanished off-shore in a storm as they were returning from the Bahamas on his yacht.
The restaurant in Palm Beach was just re-furbished. Still, as Board-O said, there are better places in the Palm Beaches to try, especially if you want seafood.
The Jupiter Charley's Crab closed down a few years ago.