Everyone I know who has traveled to South Korea says it's an awesome country full of ultra-modern cities, amazing natural wonders, and people who are happy to have visitors in their country.
On the other hand everyone (but Dennis Rodman) who has visited North Korea says it's a stark, concrete s#%thole where visitors feel like everything is staged and they're followed by secret police who don't bother to hide their presence.
Lithuanian world traveler Jacob Laukaitis went on a "strictly guided 7-day tour" of North Korea in 2016 and found the experience to be as surreal as you'd expect. He then swore to visit South Korea a year later and compare the two trips, and let's just say it was like night and day.
-Via Laughing Squid