I used my trusted old SH transport card for the airport link line, I did not see how much it subtracted from the card, but it was not much. The Didi trip after came to around 17 RMB. All in all probably the cheapest alternative.
If I had not fumbled around with the Didi issue it would also have been the fastest I think.
I will probably do the same again if I need to go to straight the office right away after landing.