KEB seems to be the best bet because of those features and because foreigners seem to have good luck getting international debit cards (other banks seem to be even more hit or miss, mostly miss).
Cell phones . . . somebody else will have to advise. I got my contract in 2005 and have been on the same one. It's a monthly plan through LG, set up by one of my then-coworkers, but I think I'm paying too much. From what I've heard from other teachers, though, there are a bunch of different plans available, including monthly plans for those who don't use it very much. That'd be ideal for me, but I don't have the energy to change it at this point.
A lot of places will charge you a deposit when you first buy the phone, refundable when you cancel your service. It's to protect against people who don't pay their bills and don't cancel their service. When I last checked, LG wasn't charging this---I didn't want to pay b/c I was a customer for over two years---but it also depends on your phone. The phone I wanted to buy would have required this deposit, so I settled for another one.
But I understand the need for these deposits, because too many people just leave without thinking to cancel their contracts. I was just going on principle, since when it was time to replace my phone I had already been with LG for 2+ years.
Anyway, LG also won extra points in my book b/c they send me the monthly bill in Korean and in English.
