Just to follow up for other folks that find this thread, TSA flat out says the screening on checked baggage will damage film. There is a good article on transporting film through airports at TSA dot gov. Unfortunately I can't post a direct link due to the rules of the site but just search for "traveling with film" and you will find it. Back when I shot film I would use the large size ziplock bags to hold about 20 rolls together. That was easy to take out of the carry on bag and asked to be hand checked.