Well this is how I look at them. You have to eat, DH wont stand in line at the parks for character meets, so we do character meals. SO we do as many as we can.
Chef Mickey and Crystal Palace are buffets so lot of variety. The characters come to the tables, so you do have to be careful to time your trip tot he buffet line. Both esp Chef Mickey have napkin waving and other hoopla like that.
Garden Grill is much more laid back, the restuarant rotates very slowly so you can wind up in a differnt location then where you start. The meal is served family style with a kids meal as well. They bring you more of whatever you like and our server kept the plates coming. It isnt as hectic so it seems like you get much more interaction with the characters.
Good luck and have fun.