My reason for preferring Suh at the time: A DT doesn't necessarily require quality around him to succeed. I worried we didn't have the supporting cast to help a #1 overall QB succeed. (And that still very well may be the story of Sam's career unfortunately).
So yeah, all things being equal, you'd take the QB. If you were looking for likelihood to produce though, you'd go with Suh.
This was precisely my argument for wanting Suh.
The Rams offense was old and deteriorating back then.
Sadly, I was right. Shurmur devised ultra-safe plays that got the ball out quickly and minimized potential for mistakes on Bradford's part. Heck, it got Bradford OROY.
I remember fans being so upset with the "dink-and-dunk" plays, but - given the talent surrounding Bradford - it was probably the only route they could go. That seemed to be proven when McDaniels came on board and put in long developing plays that exposed a very bad Oline and poor/young receivers. Bradford got hurt and had a pretty bad year.
To this day, some fans blame Surmur for "ruining" Bradford with the dink-and-dunk. Not sure whether to laugh or cry when I see Schottenheimer doing similar things.
I liked the idea of drafting a "franchise QB", but worried that he wouldn't be able to realize his full potential with what we had on the offensive side of the ball.
5 years later and we're still citing missing pieces on offense as potential reasons why Bradford hasn't live up to his potential.