The link I posted earlier is to a really interesting (analog) photoblog run by an American living in Tokyo. He does the kind of street photography exhibitions I want to do and one of his recent directions is a lot of Instax work.
Look around on that blog for his links to it, goes back about a month or so. I think it's an entirely valid pursuit...and further to the Polaroid 360 camera I mentioned, IIRC it was the one Patti Smith used for many years in her journeys.
Those images were part of a big exhibition during the CONTACT festival in Toronto: http://www.ago.net/patti-smith-camera-solo/
Best of luck! I'd love to explore the camera mall in Shanghai with you, and especially to wander the streets with my own camera. I've had a lot of fun (and financial hardship) from my trips to Wukesong in Beijing.
Shanghai's a fascinating place. You might be interested in a photobook by a journalist named Howard French, called "Disappearing Shanghai". And of course, a wonderful book by Justin Guariglia named Planet Shanghai.
Best of luck...