I'm taking my 5D III kit on a trip to Iceland and my old Lowpro bag won't do. I'm looking for a way to carry my 5D III, wide zoom, telephoto, flash, and 50 mm lens. I also want room for filters and batteries. In other words, I want to take a modest full one-body kit. It's important to me to have maximum protection from the hardships of carry-on air travel and maximum stealth. I don't want to advertise that I'm carrying a camera kit. I've narrowed it down to two options: 1. Thinktank's Urban Disguise bag OR 2. Getting a Crumpler Haven XXL to put in an ordinary day backpack or shoulder bag. I use a Crumpler pouch for my Fuji X100 and have been very pleased-- and I've seen the Thinktank and am impressed. Opinions and experience from owners of both options would be appreciated. I'm especially interested in which would be better for air travel.