korean language program in Korea

[iDoof]

Can anyone recommend a good Korean language program in Korea?

Most important to me are:

1) that I learn a lot from the program...
2) that I have ample opportunities to mingle with Korean people, not just with the other non-Korean students...

I hear lots of things about the program at Yonsei and the one at Korea University. I would love to hear an inside impression of either program, ideally from someone who entered at the intermediate/lower-advanced level.

Any help or resources are greatly appreciated.