If we're talking about fried chicken restaurants in general, Mrs. Knott's Chicken Restaurant wins for me, hands down. There's nothing like finishing off a fantastic chicken dinner with a slice of boysenberry pie.
If we're just focusing on chains, my favorite is Chick-Fil-A. The sandwiches are quite tasty and not too greasy, and they have a decent selection of breakfast foods, too. My one complaint is the price - but you get what you pay for.
I also really like Raising Cane's; I tried it for the first time when I visited AZ this past New Year's; great food, great service, great pricing. They recently expanded into CA, but the closest one is an hour away.
KFC and Popeye's were pretty tasty, but my stomach wasn't a fan of either.