I am starting a campaign in Seoul, South Korea. I was doing a study abroad here, and some guys grew nostalgic of DnD days. I used to run campaigns in DnD2e to DnD3e using the Mystara system (Karameikos and Soderfjord Jarldoms areas).
I wanted to run a game, and chose Pathfinder because the start-up time to get a game running was the best with Pathfinder. This is because I am familiar with DnD3e (and 3.5e) and I can order the PDFs. I must say I am impressed.
Other thoughts, is that there are tons of great DnD3e and d20 material out there, that I am considering using as the campaign gets going.