I've seen him live.
I see a lot of stand up and rate him very good, but not quite great.
I am pretty tough though on any form of shock humor and expect the comedian to not just rely on the shock value of saying something, few would say, to get a laugh and instead i really expect a really good joke to underlie it. Meaning if you took the shock words out, it should still be funny.
He mostly passes that test. Builds good stories, but is bit to reliant on the shock value, at points to get my top rating.
BUt that is just me. Comedy taste is super objective so just watch some youtube standup he does.