Nobody at any airport in Canada / Victoria BC and Alaska agreed to hand-checking of my sister's carry-on kit that included one old AF compact film camera. I gave her a roll of Provia 400X and two of Provia 100F; none were affected despite having passed through a total of 16 X-ray inspection points over 4 weeks (including ports visited by the MS Zuiderdam) (!). However, two SD cards for brother-in-law's digi camera were corrupted and we had to contact the photo store in Victoria BC to get copies of the files posted to us (she'd gone there to have "postcards" printed from the card). So... a positive reinforcement for film that has come through shining, but a question mark on the security of SD cards.

Now, I think it would be very fair to say that Customs around the world are aware of the concerns of film photographers and they are up to date with knowledge as to how safe that film is passing through X-rays. I cannot see anything happening that would cause a catastrophe unless you are running through Delta P3200, which I know will fog after 2 passes — and Customs do acknowledge the risk of X-rays to high speed film, so hold it up to them. No harm in asking for a hand inspection but I doubt you will, or should be afforded, one given that you could potentially be holding up a queue of impatient and irritable people.