H-Town makes a great point of not discounting any lower draft pick, and id like to add to that because you cant count on any high draft pick as well.
From the first pick of the first round to the last pick of the last round, every single draft pick is always a question mark.
2nd round All Star team
late round impact players
Tom Brady 6th round 33rd pick in 2000
Asante Samuel 4th round 23rd pick in 2003
1st round bust
Pacman Jones 1st round 6th pick 2005(when u lose an impact player for a year, thats a bust)
David Carr who was 1st overall in his year
not to mention theres a reason the Detriot Lions have continued to pick WR in the first round, they kept failing(hopefully calvin changes that)
This of course is just a few examples of each, you could fill this whole thread about first round bust and late round stars...all you have to do is look at your teams draft history to see it yourself.
http://www.nfl.com/draft/history/drafts
In 2005 the jets had no first round pick, and we got Mike Nugent, Justin Miller, Kerry Rhodes, and Cedric Houston in 4 of our 8 picks. 3 of them played in all 16 games 2006, Miller went to the pro bowl, Rhodes tied the team with interceptions, Nugent is pretty clutch and Houston(weakest of the bunch) still came through 8/16 games because we were really tight on RB. Compare this to 2001, when only 1 of our 6 picks was impact(1st round Santana Moss), and was later traded.