Sapp played 3T at Miami lined up outside the guards shoulder in the B gap. Payne played NT at AL lined up right over the OC or in the A gap. I'm not sure how you get to Allen who played DE, et al helping free him up. That is not how the front works. He 2 gapped alone in the middle mroe often than not.
There is no question at all that Payne can be an outstanding NT holding up against constant double teams and getting penetration. The question is how how he would perform isoed outside the guard as a 3T.
I find it quite easy to compare the two physically. They look the same in pads with their low cut 6'2" 310 lbs frames. I am higher on Payne's quickness then you guys are but we will see how he shuttles and jumps here is a few. All told I think his size, cut, natural bend, quickness, and strength lend to an extremely high upside.
1. Allen didn't just play DE, he also played inside quite a bit, especially in his final year.
2. Tomlinson was the NT last year. Payne played some 3T but still didn't get good numbers playing "3T isoed outside the guard"
3. Sapp was about 280lbs coming out of college, Payne was 350lbs in high school dropping down to a lean 310lbs. But there's still about 30lbs difference.
4. What does natural bend have to do with an interior lineman? Are you projecting him as an edge rusher.
He's young and ridiculously powerful and has a lot of talent. I agree he's got a good variety of moves and Alabama use a lot of stunts etc that would suit us but IMO he's more Jonathan Hankins than Sapp. Maybe he can push back up in weight and his ceiling could become Damon Harrison because he has that sort of intelligence, but I guarantee you he will not be a consistent double-digit sack guy like Warren Sapp. It's not the way he plays, they are nothing alike.