I know James Joseph Dresnok did this, only in reverse, but most North Koreans who defect go the long way around, China, Mongolia, Laos...
Noting in the article about exactly how many people have crossed the DMZ. According to article, more than 29,000 people from the DPRK have defected since since 1953, mostly by way of China. That's about 460 a year.
BTW, my Chrome threw up an error message asking me to call a TFN and locked up my browser. Anybody else have this problem? (Running virus check and CC Cleaner now...)