Is Boxberger ready to be a big league closer?

With the Free Agency of Francisco Cordero, there are rumors that the Reds may promote a closer from within. I like this strategy a whole lot better than overpaying a big name like the Rangers did with Joe Nathan and the Phillies with Papelbon. This strategy has worked for teams like the Rangers with Neftali Feliz, and even the Red Sox with Papelbon several years ago. The prevalent name in circles that follow the Reds is Brad Boxberger. So with only minor league statistics to guide us, can we see tell if he will be a good Major League reliever? He has spent 2 seasons in the minor leagues and in 153.2 innings, and has a -4.71 PE (with BABIPs of .233, .241, .392, and .329). More importantly, he threw 27.2 innings for the AAA affiliate of the Reds, an International League team. This means we can use the metric previously formulated here. Boxberger had a -6.03 PE and -5.8 Adjusted PE, predicting that he would have somewhere between a -3.5 PE to -3.27 PE in the Majors. Of course, negative is good, but for comparison, Madson had a -3.44 (adjusted) PE in 2011, Marmol a -4.65, and Papelbon has a career -5.3 PE. So Boxberger projects to be among some of the elite closers/relief pitchers in the game. There are a couple of questions though, the above is a very small sample size, and his BABIP was extremely low at .233. FIP still has him at a 3.16 (that is why there is much of a change in adjusted PE), but he walked nearly 5 batters every 5 inning. This makes you question the validity of many of the AAA statistics. However, his overall minor league statistics (a decent sized sample), and his success in the very hitter friendly Arizona Fall League (-5.68 in 13.1 innings, obviously another small sample size) lead me to believe that it would be much smarter to use Boxberger as a closer than spending a bunch of money on a free agent closer (frankly, the market seems to set up to overpay closers). If Boxberger doesn't work out during the season, you can always try to trade for one (if the Reds are in contention). But even if Boxberger is only half as effective as Papelbon in 2012 (he projects to be better than that), he will still be making 3.8% of Papelbon's salary.