Im going to say OEGBs too. My cochins never were really reliable broodies, but once you give an OEGB eggs, you need a pry bar to get her off of them! And they are PROTECTIVE mothers too.
cochins cover more eggs, are broodier but OEG are more protective mothers. So I they are going to be around cats, use OEG's. No predators and in a protected area go w/cochins.