I agree with you...which is why I just don't see the Saints drafting him. The Saints need a player with a higher probability of success at 15, even if they drop down into the late-20's/early-30's I wouldn't see the Saints taking him for that reason.
Another comparison that might be made would be with Bruce Irvins, last year. But again, Irvins is a larger player, at least 10-15 pounds heavier, and maybe a tad bit faster. And Irvins is in a special situation in Seattle in that he is a playing a very specialized position, just rush the passer. Not many teams can afford that luxury.