Not many drawbacks, QF and CX don't require ticket reissue after
a date change, and you can still view your QF (and unchanged CX) flights online. Just pick the tickets up a few days in advance in case there's a delay
issuing them (there probably will be).

tips:

• get QF to add your email address to your booking so you'll get notified in the event of flight changes to the QF flights
• if the paper tickets are handwritten then make sure they include all the taxes you have paid, especially PC1 and PC3, otherwise you may get hit again at the airport (we did get hit).
• Date changes you make to the CX flights won't be reflected on checkmytrip.com, when making CX changes get them to email the new itinerary to you.