hello,we'll be reach HK & staying at Empire hotel causewaybay(Tin Hou)after our macau trip.we plan to buy 2 single Airport Express journeys and 3 days of unlimited travel on MTR, Light Rail and MTR Bus.And will use the airport express on our day of return. within these three days we plan to go disneyland/ngong ping/kowloon. Just want to know is it worth to buy this airport express pass in our case ?is it cheaper to purchase online?thank you