I think it's gonna be Barkley.
I think that Smith has more obvious physical ability, but there are real questions about offensive system he's in and his performance against real competition.
Barkley's a good bet to at least be a solid NFL QB. Intangibles are all there, and he's run a pro style offense for 4 years.
I think people are making too big of a deal about his arm being weak; it's not weak, it's just not elite. He's super accurate, though.