The 10 year Chinese visa does exist, but only if you are lucky enough to be the holder of an American passport! Canadians may also be granted a visa for anything up to ten years but this can vary. It's worth noting that this can only work with M, L, Q2, S2 visas. It's also worth noting that for each trip to China the person must exit the country again within 60 days. That could simply involve a trip to Hong Kong, Tokyo or Seoul for example but you must exit the country 60 days after the first day of entry.