6 years too late... I was in Sierra Vista in 2001... ah well. Staying in Bisbee, and zipping across the border at Nacho Sonora to pick up cigarettes, confused the h@ll out of the border patrol, as I was a Scotsman resident in Australia crossing into the US from Mexico - glad it was before 9/11 or I am sure there would have been more questions asked.
cheers
Doug