What do you think would happen
Kim Jong-Un would have an updated power grid?
I have a feeling in order for the Korean peninsula to be reunified China is gonna have to play a role. Not in an interventionist way I should mind you. Currently China has a policy of sending back North Korean Refugees. If they one day decided to not send back refugees anymore then North Korea would go the way of east Germany.
Most people compare a Korean reunification to the German reunification, but i think it is a little more complicated then that. German's were nowhere near as brainwashed as the North Koreans. South Korea's Economy is not as strong as former West Germany's.
There will be a lot of people needing to adjust to capitalist life. There will definitely be some improvements, such as improved access to good, more food, more business opportunities, electricity, etc.
I have another prediction, if the reunification is chaotic then there is a chance that Korean Organized crime can mushroom, much like how the Russian Mafia grew after the disintegration of the USSR.
Hilarity would ensue.