This all depends on your point of view and your place within the society. If you're a jew, the answer is definitely the 3rd Reich because. The North Koreans kill a lot of people and repress and starve a lot of the rest, but they're not actively trying to kill one particular ethnic group. However, from the perspective of the average citizen, North Korea is in many ways worse.
If North Korea was as strong (relatively) as Germany was in 1941 or so, they'd conquer SK, much of China, various islands, etc and threaten Japan. They might look a lot like the Japanese of WWII.