If you need a heavy duty bag, check out this carbon fiber bag. It’s super light (under 3 lbs) but very sturdy, and, as an extra plus has that undercover/cool look about it. The briefcase (below) is also worth considering.
Waterproof carbon fiber sailcloth
Made in the USA
size: 26″ x 11″ x 12″
Carbon Fiber Briefcase, $140.00-$145.00