@Cageybird, I agree that gyros and donairs aren't really interchangeable, but I happen to like the donair meat a little more than you do. The lamb in traditional gyro meat is something I could live without. The donair meat is more like a really good meatloaf mix with an added kick of Mediterranean spices. I think it's a better dining experience if you don't try to compare the two sandwiches side by side.
I know that many health departments put a lot of restrictions on the use of vertical rotisseries, like the ones used for gyros and donairs. Someone has to shave off the meat off the cone when it becomes browned, and then cook it again on a flat top or in a frying pan.