Best cover-2 corner in the league? Maybe. But he has Charles Tillman to fight for that title.
I just feel like comparing a cover-2/slot guy to an outside man guy is basically like comparing a running back to a wide receiver, or a tight end to a wide receiver or a 5-tech DE to a 7-tech DE. They're just different positions.
Winfield is asked to cover about 1/6th of the field, whereas Sherman and Revis have to cover 1/2 of it. Winfield is great at what he does, and the run defense aspect of it makes it just as tough or nearly as touch as Sherman and Revis trailing WRs all over the field, but it's just entirely different.
I don't think you can properly compare them. I think the argument at hand is best shutdown corner, and Winfield is not a shutdown corner, nor has he ever been.
I was entirely kidding man. It's stupid to argue this, really.
Personally, Revis is the best corner in the league. Sherman is probably 2nd, maybe 3rd. He had one good year. It may say that Revis has x pass deflections, and Sherman has x pass deflections, but if you watch Revis' pass deflections, they are absurd ones that he has no business making, where it's a perfectly thrown ball.
Sherman is no joke, but the dude is just unbearable, really.
The two will never go against each-other. It's like when people say Brady beat Peyton. He didn't. He has never lined up against Peyton Manning on a single snap in a game they have both been a part of. I hate Revis, I hate Sherman, I'd rather have Revis on the Bills than Sherman on the Bills. But in two years, that could flip, who knows. Nnamdi was fucking amazing in Oakland, went to Philly, and was exposed. Revis is in a blitz-heavy scheme, and more often than Sherman is left on an island.