There is a world difference between Green Minibus and Red Minibus in Hong Kong.
Some tourist may not know the difference. Green Minibus accept payments by cash or Octopus Card, whereas Red Minibus only accept notes and coins as payments. Minibuses are mainly for locals so it is somehow inconvenient for tourists with different language backgrounds except for Mandarin. Minibuses are not recommended to tourists unless the minibus you ride on traveling between two terminus plus some stops are not easy to locate unless you are a local!
Drop-off service is suitable for transfer from/to Naples airport or railway station to Sorrento, Positano, Praiano, Amalfi, Ravello or the other towns on the Amalfi Coast.