Once I went to a 'cycle touring' party, and I met a guy who cycled 9 months thru China (on a 700c bike) with his wife (on a 26"). She could get tires and tubes at any bike shop. but when his tire blew, they had to take a train hundreds of miles to a European bike shop in Hong Kong in order to get a replacement. He said when he got back he sold his bike and bought a 26" touring bike.