I use cast iron and carbon steel for high-temperature cooking. If I really care about the non-stick-ness I'll usually use nonstick. But nonstick doesn't char well (and isn't safe). So when I want a serious sear or browning, I use iron & stell.

Problem is, if something burns on, it burns on hard. Soap doesn't really help. Water and scrubbing mostly do, but they don't completely get it off. I can't even tell when the remaining patina is seasoning and when it's just gunk -- until it becomes rough to the touch, in which case it's obvious, and I scrub hard.