I can second Jiejie's experience with ctrip bookings. I use them 2-3 times a month and I don't even bother to print their confirmation.
Just show my passport at check in. Never any problems!
On top of that, once you have registered your mobile number, calling them will result in automatically recognizing you and showing your itinerary on their display. the agent is ready to help you changing / modifying or canceling your ticket without any hassle.