Booked air ticket from Zuji.com

A few days ago, I booked a return air ticket to Shanghai via China Eastern at S$523 from Zuji.com, this is the second cheapest I could find and it is direct flight. The cheapest one is S$511 and required a transfer at Philippines for half a day; I just felt it not worthy. Today another colleague introduced me another website airfares.com.sg, and from there, I can get the almost same air ticket at S$640 via Singapore Airline, maybe I will try that for my next trip.