The Safari Club has worked really well for us. Used it at T-Rex and RFC at
Disneyland for seating and free appetizer or reduced meal cost.
"Priority Seating ...
For parties of six or less, seven days a week. Priority seating (based upon availability) on a walk-in basis ensures you quick attention and the earliest available table."
"10% Off Entrées!
For you and up to three of your guests, or a free Chef's Appetizer of the Day with the purchase of an adult entrée at participating Landry's Restaurants nationwide**."
I love that one at RFC, so hubby can get an entree and I can get their pita quesadillas (without chicken) b/c I looooove them.
But at T-Rex they had this whole list of things, and we got a reduced cost on some appetizer combo thing.
I'm sure if it's drastically busy you're either going to still have a long wait even with the priority seating, or they might curtail it, but I'd still try!
Also, you can call RFC or T-Rex directly to get reservations, if you can't get anything through WDW's system, if you want to get an ADR.