My personal preference is Surtain because of the lesser chance of a bust. Horn may indeed have the higher ceiling, but he also comes with more risk. At #10 overall, I prefer the safer pick.
Hate to say it, but the Cowboys have to go with the safer pick. The downside of Horn not "panning out" is bigger than the upside of Surtain being ready to go NOW. Physical traits are in born for the most part, but technique takes years to develop. For example, if Horn bites on a double move, the receiver is going to be long gone, no NFL receiver is THAT much slower than a speedy cornerback, even a 4.6 forty receiver covers several yards in a second or two, Horn at best might be able to chase him down after a 30-40-50 yard run IF the catch is made inside their own 50, but a catch like on Dallas' 30? Touchdown. Technique keeps the catch from being made, the ball being thrown there anyway or yardage restricted to where the actual catch was.
It's a minor thing, yes, not saying Horn isn't an excellent prospect. But with Gallup, Williams, Gregory, Armstrong and others being free agents after this year, and Neal, et al on one year deals, Dallas has to make a push for the SB, even if they think they're not "ready for prime time" or at the least see how players respond when the pressure's on to get to the playoffs or play in the playoffs. Don't get there this year, going to be a LOT of changes next year....