I'm looking for a bag that will be durable for the trails, good for commuting. able to hold a set of scrubs, nike shoes, a few medical supplies such as trauma shears, stethoscope, ETC. oh, and a flat repair kit. This bag will be used mountain biking, commuting, and rides on the motorcycle.

I was looking at the camelbak HAWG, I have never seen one online but it looks pretty nice, got good reviews. anyone have comments on how much crap they can fit in it? Or should i just look for a backpack that holds a fluid reservoir? thanks for the help