I think there's certain games where GBo could carve up teams with his legs relentlessly but I think Big12 defenses will figure that out and force him to win with his arm. And it sounds like Retzlaff is the better passer. Plus Retzlaff runs enough to keep the defense honest.
So as frustrating as Retzlaff is, I think he's got the higher upside. We saw @ SIU that he can make big throws. If he can get over being rattled against better opponents he could actually be a decent QB