Are there any foreigners who lived in North Korea and what do they have to say about safety?

Aliou Niane lived and studied for 5 years in North Korea. You can read his story here. When asked “Did you ever feel you were in danger?” he responded: “Not once. I never felt I was in danger in the sense of the Western world. But we all knew we were valuable propaganda assets to the Communist Party in North Korea and to the Guinean government which was expecting aid from the North. To show people how wonderful North Korea was, the propaganda media would tell North Korean citizens that they had very good lives. As proof, they were told to just look at how many African students were living and studying in their country.”
Even for an array of severe crimes such as listening to foreign radio channels Aliou never got punished simply because he is a foreigner. Foreigners are used by the government to spread propaganda whenever possible.
Other foreigners have been questioned by the police and banned for crimes such as taking pictures without a guide, being an undercover journalist etc. Note that while these foreigners got back safely to their country, there is almost certainly a North Korean civilian or guide who did get punished for not reporting or failing to guide these foreigners properly.