That's a tough one. They're all good. We have all 4 locally (or in the next town) here and I have been torn on which to get more than once.
Bonjangles chicken does tend to be on the greasy side, yet the "southern cajun" IS quite good and the biscuits are buttered perfection.
KFC original is pepper 'n' salty goodness and will always be a top contender in my book.
Church's is great when you want to spend less and still get good chicken (and I love the ears of corn you get).
Popeyes spicyness is a welcome refreshment from the frying vats....
It's hard to pick a clear winner. You just can't go wrong with a dead, breaded and fried bird.
BUT, if any of you ever make it to Columbia, SC you should try Zesto's chicken....it fuckin rocks.