I'm in search of a new backpack to replace my old laptop messenger bag (great bag - Boog, but it's falling apart after 6-7 of everyday use). I'd like to start riding my bike to work (5 miles each way) when spring actually decides to show up. I'm looking at the Escapist bags from Osprey. Does anyone know if the 20L version will fit my laptop @ 15.4 inches? I know the 30L version will, but nobody seems to mention if the smaller bag would? I'm not worried about a "dedicated" laptop compartment, as long as it fits, I'm good. Also, how's the body fit on this backpack? I'm a pretty big guy with large chest and shoulders.