I can only go on having been there on holiday. I was living in Japan at the time. I'd liken Korea to a 'Chinesey' version of Japan
I had a lovely time. The food is great, there is a fascinating culture and history and lots to do. In the space of a week I was rummaging around in markets and antique shops in Seoul, to hiking in the mountains around Kyongjou and staying in traditional style inns. I reckon a year there would fly by, working or not!
p.s. Transport was absolutely fine. The only point that stands out as memorable is the MRT carriages in Seoul are huge, they must be 12' wide!