Might have said AMC a few years ago just due to the strength of BrBa, Mad Men, TWD in its prime, and BCS...however, they are also known for generally fukking with the shows on their network and besides BCS they don't have much going on. FX deserves a ton of credit for basically being the first network to bring gritty HBO style shows to cable TV. The Shield is one of the hardest and most underrated shows ever. Nip/Tuck and Rescue Me both had solid runs. Justified was fire. So was Fargo. Not to mention they currently have Atlanta, Always Sunny, AHS as well as ACS.
Breaking Bad is in my top 2 shows of all time along with The Wire, and Better Call Saul is damn near as good as Breaking Bad. But I gotta rock with FX on this one.