I think he compares favorable to Bruce Smith and Reggie White of recent memory. He as out performed JJ Watt. He reminds me of another DT that was undersized named Alan Page one of the leaders of the Purple People eaters. Alan Page, Bob Lilly, Merlin Olsen and later Mean Joe Green are all players that Donald compares favorably too. Off the top of my head they are the best I have seen and he certainly fits in this group.