All taxi drivers in Shanghai are rated by stars. The more stars they have, they better they are - in their efficiency in getting you to your desired destination via shortcuts. Their ratings can be found on the windscreen as well as in the taxi, on their nametags. Certain 3 stars taxi has a little sign right below their rearview mirror. Consider yourself lucky if you ever get on a 4 stars and 5 stars taxis in Shanghai.
Best taxi company is Da Zhong (turquoise colour). If you ever feel like the taxidriver has taken you on a merry-go-round, show him that you're upset and ask for receipt - for sure he will give you some discounts.

