I'm a sunshine pumper, so take my opinions on this with a grain of salt.
Bradford has always been disappointing, but look who he has played with.
RBs: He had Steven Jackson for his first 3 years, but Jacksons best year is worse that Peterson's worst year. After that it was Zac Stacy. In Philly, Bradford ran the wacky offense.
Bradford has had rushing offenses ranked 25, 23, 19, 19, 20, 14. During the same timeframe with Petersen, Vikings have been 10, 4, 2, 8, 4. Bradford has never had to be a game manager. He has been required to carry the load for teams with poor running games.
Luckily Bradford was surrounded by amazing wide receivers like Danny Amendola, Brandon Gibson, Brandon Lloyd, Chris Givens, Jared Cook, Tavon Austin, Jordan Matthews, Zach Ertz. There are 2 or 3 potential Hall of Famers in there.
Seriously, though, what a garbage group of receivers he's been surrounded with. When you have no running game and Danny Amendola is the best WR you've played with, not wonder you're going to have lackluster stats.
Oh, one last thing. The best defense Bradford ever had him was ranked 12th in the league in scoring defense and 14th in total defense. Vikings last year were 5th in scoring defense.
So Bradford will have a far better Rushing game, a better defense and recievers just as good as any others he has played with.
First round pick is a lot to give up, but hopefully its a bottom 5 pick.