Hi sistrunkt
Thank you for your request.
For your trip, I recommend the group ticket. It is 30% cheaper than the normal ticket. We advise you to allow enough time at Zurich airport. If you miss the train, you can use the ticket via the same route but the seat reservation is no longer guaranteed.
You will find the information and the possibility to reserve here.
I wish you a nice weekend.
Kind regards
NicolasK