I can imagine how cramped the seats are & you have to buy food & drinks etc...I flew to Taipei on ScOOT...boy, it sure was cramped. I flew once by SIA HK in an Airbus A380...it was worth the money. I use AirAsia for short trips , even that, I try to fly by regular airlines, for example, I go Phuket...I pay to fly by Silkair...
If I am to fly 4 hrs or more..regular airlines will be the way to fly...you sit in cramp seats for so many hours...you get a feeling, you are being shipped as "cattle in the cargo hold"..