The t-shirt was definitely an option they had when I ordered just a couple weeks ago...this seemed best to me because on the customs declaration form it states t-shirt, and just by holding the package u could feel it was in fact a t-shirt...I assumed this made it easy to pass along and not inspect too much.
A dvd could contain a whole lot of things in it, and a zippo contains possible liquid in them. I'm sure they have plenty of a success rate with both methods, just figured the tee was best. Plus now that 14 bucks I paid extra to conceal it in a t-shirt just really wound up being me paying 14 bucks for a cool t-shirt.