Metro line 10 runs from the airport to the city, NO traffic jam, EASY connecting. The whole trip from the airport to Mrs Panda costs only 5 Yuan in 30mins.
I(Kevin Liu) have experienced it and it was easy to find even if you are new in Chengdu, just follow the huge blue signs on the floor at the airport. The metro has 2 stations at the airport both at the Terminal 1 and Terminal 2.
The only negative way is that you will need to take two metro lines to our hostel , but the metro does not run for 24hrs. The connecting metro line 3 stop running at 10:30pm. If your arrival time is later that this time, please take the shuttle bus line 1, as it runs the whole night until the last flight lands in Chengdu.