I hadn't even though of crankarm clearance - I figured the manipulated chainstays would negate this problem. They're 172.5 cranks, and with the 170s on the road fix and straight round stays the clearance is tight - about 2mm, but I haven't had a problem with it.

Maybe I'll start looking for cheap track cranks, but I really don't care to spend 200 bucks on a crankset just because it's a track set. I mean, would that even matter? It's the chainline with the bb and crank that matters, right? I totally hadn't considered that the Surly might be made for short crankarms since it's a street bike - I would run 180s or bigger if I could find them.