Bonderman's an interesting guy, he came up to the majors throwing 95-98 mph fastballs but has clearly lacked that velocity for 2 years now. His fastball is now 90-93, not enough to really make hitters uncomfortable, and it doesn't seem to have great movement.
His slider is clearly his best pitch but it's too predictable, and his changeup still remains a relatively undeveloped pitch. Bonderman's a very disappointing prospect in general. That being said, I picked him up off the waiver wire and would still spot start him against exceptionally weak teams, especially ones that struggle against righthanders.
Here's a weird question: how concerned should we be about Verlander based on what has happened to Bonderman? Like Bondy, Verlander came up to the majors super-young and seems to have already slowed down in terms of velocity. I watched Verlander's debut v. the Rangers and every fastball was 97-99. I felt his velocity was very consistently 95 mph in his first season, a bit slower last year. This season it has been 91-96, although averaging closer to 92.
Verlander has a top-shelf changeup and a great curve, so I think he obviously holds up better than his teammate, but it's a worrisome comparison nonetheless.