I have the Chrome L (metropolis?) and I can fit a good amount of 12"s in there. Whenever I go back and forth from Chicago to Boston, I always seem to bring around 25-30 LPs back to Chicago and I have no problem bringing them back, save for discomfort of that weight on my shoulder.
My buddy just got the REload Courier and I have to say thats a pretty sharp looking bag, not that this has any relevance right now, but its still pretty damn nice.