To each his own, I suppose, but to me Papa Johns is the worst (and this might just be a matter of the store you solicit rather than the chain).
Papa john's pizza.
-- Crust that could be used as an inner tube
-- Cheese that tastes like somebody thought that dripping hot candle wax over the crust would be a good substitute.
-- Sauce so sweet it could be used as a topping for pancakes.
-- Sausage with so much cereal it could be served in a bowl with milk for breakfast
You can watch them make it from scratch.