Strasburg - has the best stuff of this group (maybe toss up with Harvey) but his long term durability is an issue for me. also doesnt not seem to have the mental fortitude of Bum, often showing visible frustration on the mound.
Sale - cannot see him having a long career.
Miller - has dominated in brief MLB career but really only a 2 pitch guy, and how many of those have sustained success? will need to develop a better 3rd pitch to have a shot.
Fernandez - Incredible to be doing whats hes doing at 20, but hes been in pro ball for such a short amount of time that nobody really knows how good he could be. enormous potential for sure.
Harvey - 4 good to great pitches, elite velocity, and showing remarkably improved control compared to his previous career. also classic power pitchers build that screams durability. my 2nd choice and would be my first if not for Bums much longer track record of excellence
Bumgarner - my choice because he has been very good for several years now, and like others have mentioned there are no red flags for injury. at least 3 of the other guys have a higher ceiling, but he is most likely to have a long and successful career, as hes shown he does not need elite velo to be very effective. also (homer alert) i have seen around 80% of his MLB starts so its easy for me to see just how talented he is, and how composed he is on the mound. nothing phases him