DO YOU ever have anxious moments at the immigration counter? 

I do. I don't know if the immigration officer is going to give me grief or let me through without asking a single question. 

At the Shanghai airport last week, it was a pretty smooth clearance. 

So smooth that I rated the service, "Greatly Satisifed" by pressing a button. 

Yes, the Chinese immigration authorities had automated customer service feedback. 

On the left side of each counter, was a box - about 10 cm long and about 8 cm high - with four buttons: Greatly satisfied, Satisfied, Check too long, Unsatisfied. On top of these buttons was the service number of the Immigration Officer. 

No one was compelled to respond, but with your passport in the officer's hands, it would be nice to respond with a good rating.

What a clever way to collect customer service feedback. It is easy to do and the results can be tallied at the end of each shift. 

It also subtly pressured the officer to do his best quickly which is a productivity measure as well.