I agree with Phil. I've gotten rid of all my Pelican cases, and have several Porter Cases (incl. one of the shorter ones, although I typically use the full-size one) -- I never travel without one. (BTW, I suggest getting one that has a felt liner.) In addition to being great for hauling camera gear around, the P.C. serves as a great hand truck - you can stack 200lbs on it (i.e., your other carry-on plus both checked bags!), and pull it all around with one hand! I never have to look for luggage carts or porters, and have probably paid for my P.C. just by avoiding those alone!
Whether you use a Pelican, P.C. or something else, I think it is VERY important to always carry one of those little nylon daypacks that folds into its own pocket so it's only about the size of your fist. That way, IF you're ever stopped at the gate because one of your carry-ons is too big or heavy, you can transfer your valuables out of that carry-on into the nylon pack and carry THAT on, gate-checking only the (nearly empty) case that was in violation. I've only had that happen a couple of times (mainly Qantas flights in Australia), but the little nylon bag idea allowed me to keep my valuable stuff with me, and I've NEVER had anyone refuse to let me take on that nylon pack full of gear. B)
