Prospect Smackdown: Sean Gallagher vs. Kevin Slowey

Background and Intangibles
Gallagher: Gallagher was drafted by the Cubs in the 12th round in 2004, out of high school in Fort Lauderdale, Florida. He was considered a third round talent, but most teams thought he would go to college. The Cubs managed to sign him. He didn't get a lot of attention early in his career, but a breakout campaign in the Midwest League in '05 and a strong follow-up in '06 have boosted him up the charts. Scouts praise his intelligence, work ethic, and pitching savvy.
Slowey: Slowey was drafted by the Twins in the second round in 2005, out of Winthrop. He was drafted on the strength of his intelligence and pitching savvy; his arm strength isn't spectacular (more on that below), but he knows what he's doing. He pitched in the '06 Olympic qualifying game, and also did well in the International League playoffs, demonstrating his ability to handle pressure.
Advantage: Slowey had a higher profile as an amateur, but both pitchers have done well under pressure thus far and draw praise for their personal "intangibles", with strong work ethics and feel for pitching. Slowey probably rates a slight edge in this category because of his greater experience on the big stages, but that's also a function of being a college rather than a high school product.

Physicality, Health, and Tools
Gallagher: Gallagher is 6-1, 210 pounds, righty hitter and thrower, born December 30, 1985. He has been healthy and durable so far as a pro. His fastball was 87-89 in '04 and '05, but improved to 89-94 last year, with movement. His curveball is excellent, and his changeup has developed into an average pitch. His mechanics are usually solid but at times they will wander a bit, hurting his command.
Slowey: Slowey is 6-3, 190 pounds, righty hitter and thrower, born May 4, 1984. He has been healthy and durable so far as a pro. His fastball runs at 88-92 MPH, but his command of it is perfect and it moves well. His breaking ball and changeup are decent, but he needs to use them more often, and he tends to rely on the fastball excessively. This has worked against minor league hitters but he'll need to show more diversity in the majors and use his other pitches more. His mechanics are both deceptive and repeatable.
Advantage: Both pitchers have been quite durable so far. Slowey is a bit more athletic physically, but Gallagher has a stocky and durable frame. Gallagher throws slightly harder and has a better breaking ball, but Slowey's command is better. This is very close, but I think I prefer Gallagher a bit since he throws slightly harder and is more willing to use his breaking ball.

Performance and Polish
Gallagher: In 350 career minor league innings, Gallagher is 26-12, 2.65, with a 361/142 K/BB ratio. He posted a 2.71 ERA in 15 starts in Double-A last year, although his K/BB slipped to 91/55 in 86 innings, a sharp increase in his walk rate compared to what he did in the lower minors. He's relatively polished for his age but needs to work on keeping his mechanics and command consistent. Double-A component marks: K/BB -16 percent compared to league, K/IP +25, H/IP +8.
Slowey: In 221 career minor league innings, Slowey is 11-7, 1.96, with a 253/30 K/BB ratio. He posted a 3.19 ERA in nine starts in Double-A last year, with a 52/13 K/BB in 59 innings. Aside from needing to mix his secondary pitches more frequently, he is very polished and has superb command. Double-A component marks: K/BB +75 percent compared to league, K/IP +7, H/IP +12.
Advantage: Both have performed very well in Double-A but in different ways. Slowey's K/BB ratio was much stronger. Both of them posted above average K/IP and H/IP marks, but Gallagher's were better. Overall I think Slowey has the advantage here since all of his components were better than average, but Gallagher's weren't. The difference in command in Double-A is quite notable.

Projection
Gallagher: Physically, Gallagher isn't likely to pick up much additional velocity and is close to his physical ceiling now. He projects as a number three type starter at the major league level, a durable inning-eater type. PECOTA tries to quantify this, projecting him with a  50.4 mean VORP and 60.0 "upside."  
Slowey:  Slowey also projects as a durable inning-eater type, but more in the Brad Radke efficient strike-thrower mode. PECOTA likes him a lot more than it likes Gallagher, giving Slowey a projection of 114.2 mean VORP and 124.3 "upside."
Advantage: This depends on your perspective. A traditionalist might like Gallagher better since he is younger and throws a bit harder. But PECOTA really prefers Slowey, probably due to his superior command at the Double-A level. My own opinion here is that Gallagher's ultimate ceiling is a bit higher than Slowey's, as reflected in his stronger K/IP ratio in Double-A, but that he is also riskier than Slowey and more likely to flame out on us. Call it even.

Summary
I give Slowey a slight edge on background and intangibles, Gallagher a slight edge on tools and physicality, Slowey an edge in performance based on what they did in Double-A, and rate them even on projection. All in all I think Slowey has a slight margin ahead of Gallagher. I ranked Slowey at 33 on my Top 50 Pitcher list, and Gallagher at 38. I like both of them a lot.