Who's the better pitching prospect, southpaw Aroldis Chapman born in 1987 or flame throwing righty Stephen Strasburg born in 1988? Both are young enough to have many productive years in the MLB. Strasburg is probably the better pure prospect, I haven't seen Chapman pitch but I can't imagine his stuff being as good as Strasburg's, nor can you replicate how good pitching in college can be for a young pitchers progress. Honestly though I don't know who's better from an on the field standpoint.
One thing I do know is from a collector's standpoint Chapmans's cards have the potential to blow Strasburg's away. Why? Simple, Straburg plays for the worst team in baseball (nothing personal nationals fans, I'm simply stating that their record is the worst in the MLB at this point), while Chapman will get to choose what powerhouse he plays for. If he chooses the Yanks, Dodgers, Red Sox, Mets or any well collected teams he has the potential to make the fervor over the 2003 Bowman Chrome Jose Contreras when it was originally released and it's $200+ price tag look like nothing.
That being said this 2009 Upper Deck USA Strasburg Jersey card sells for around $16-$27 on ebay.
While this 2009 Topps WBC Chapman Jersey sells for $7-10. This is Chapman's only game used piece that I'm aware of, he does have some other Bowman and Bowman Chrome cards but this is the only jersey piece I saw.
While there is no substitute for being the #1 overall draft pick there's also no substitute for playing for a powerhouse (and in Chapman's case he gets to pick his team, well at least his wallet does) . Just as Bryan Bullington if he'd like to play on a team that gives him run support like the Phillies give Cole Hamels. Both came out of the same draft class, only Bullington went #1 to the perennially pitiful Bucs while Hamels went to the hard hitting Phils and the rest is history. One is a bust and the other is World Series MVP. I'm not saying it's all about what team you play for but getting an almost guaranteed 5 runs of support a game is nice. Remember, Walter Johnson went 5-9 in his rookie season in Washington despite having a 1.88 era in 1907, could Strasburg suffer a similar fate in 2010?
To sum it up I think the Chapman WBC Jersey is an incredible value right now considering he has a ton of potential.