There is no way you could evaluate Sam Bradford really with the Rams. He played with practice squad WRs and had bad offensive coaching and he wasn't healthy.
Based on what I see right now and even last year, I believe him to be an above average QB and if he ever lands in a good situation, he could become a pro bowl type of QB. He was close last year before he got dinged up and missed some games on leading that team to the playoffs. He appears to have a shot this year again of leading a team to the playoffs on a team with very little offensive weapons now that Peterson is out.
But they do have 1 good WR that was drafted in the 5th round which is more than he has ever had previously. You have to have the coaching and players around you to have a chance at the QB position.