I had a pretty crummy experience with Cebu Pacific back in 2010. I was flying with them from MNL to ICN, with connections onward (on a separately booked ticket) from ICN to the U.S. It was a foggy night in the Seoul area, and we wound up having to land in Busan and then get driven via bus across the entire country. The buzz on the plane at the time was that the airline had refused to spring for whatever system helps pilots land in fog, and our particular pilot was too green to do it without the help. What was supposed to be a relaxed overnight layover in ICN wound up being one of the most stressful evenings in the entirety of my travel experience.