You are almost always "safer" signing players who have experience and a track record in the NFL over a rookie coming out of college. With the latter, you never can be sure how thing will turn out. Garapollo, Bortles, Alex Smith, Sam Bradford, whoever, you know to virtual certainty what you're getting whereas Darnold, Mayfield, Rosen, even with all their talent, their success and their acclaim, are shots in the dark.