Need a good travel bag recommendation

I've already outgrown my current bag, and I'm heading to Cuba in January and need a new carry-on bag, so I thought I'd bite the bullet and get a decent backpack-style camera bag.

I'd like something that is wearable like a backpack, and can double as a plane carry-on bag.  I quite like the Lowepro Flipside bags -- the reversed design strikes me as somewhat pickpocket-proof.  Are there any other bags out there with a similar (or better/comparable) design that anyone would care to recommend?

I currently have a T3i with a 15-85, 55-250, and 50mm 1.8, and would like a bag that will let me store all three plus charger, etc, and the lens hoods for both big lenses (this was the clincher for my current bag -- once I crammed the 15-85 in there I didn't have room for both hoods). I likely won't be taking the 55-250 with me on this trip, so I can use that space for carry-on luggage if need be.

Does anyone have any suggestions?