He's been projected to go at No. 31
Journalstar
"Nebraska junior nose tackle Ndamukong Suh checks in at No. 31 on the list of Scouts Inc.'s Top 32 NFL Draft-eligible players.
. . . .
Only three DTs are listed ahead of Suh on the Scouts Inc. list: 14. Gerald McCoy of Oklahoma; 17. B.J. Raji of Boston College; and 24. Terrence Cody of Alabama."
*** Rankings will be adjusted as more and more Jrs and redshirt So. declare
Yeah, I don't get how they do this accurately. Hopefully they give them a lot of info, like who is in front and behind them, and who of other underclassmen that are eligible would be in front of them if they go. There's no way an absolute number like #31 really makes sense unless you are the last to decide.
I've heard that they do give them tips like what they'd need to work on to improve their standing, so it's certainly good to get an evaluation.