Thanks for the replies, I looked at the Star Alliance site but must have missed the promotion, it is interesting but I'm not sure it suits me.

The plan is to fly into and out of China with Emirates, then once in China do the somewhat circular route of Beijing - Xi'an - Chengdu - Guilin - Shanghai.

The internal flights are currently priced up at about 400GBP, plus as an enthusiast, I've the added bonus of having worked out that I can fly each leg on a different Chinese carrier (China Eastern then China Southern then Air China and then Shanghai Airlines), which is pretty cool.