He's got no chance. If Strasburg didn't make it, Purke isn't going to.
Im in favor of taking it slow with the kid at the start. Start him out in Hagerstown. If after 5 starts, he's killin it, move him to Potomac. I'd let him settle in at Potomac for a little while, but could see him finishing the year in Harrisburg if everything goes well.
As long as he's healthy, he'll be a fast riser. His combination of stuff and poise will get him to the bigs pretty quickly IMO.