Originally Posted by
lsquare
Does it matter where I obtain the Airport Express ticket? Yes, I always take the airport express to and from HKG. I took the bus once from HKG to Kowloon in 2008 and I would never do that again. Every trip since then has been with Airport Express to and from HKG.
I can't imagine they would know or care where you bought it if it's a ticket or Octopus card then it's a ticket or Octopus card.