We had a two-night stay in Simon's apartment, and everything went smoothly. We were welcomed by his housemate Rasmus, who showed us their place.

As stated in other comments, the bedroom is quite small, but it's quite enough if you're planning to spend most of your time in the streets of Copenhagen as we did. Just be aware that the bed in itself is a 130x200 cm, which is a bit smaller than the usual.
The other rooms were great, with a nice kitchen with everything you need if you want to cook some food (seems Simon has some baker skills by the way), a large living-room with a table and a confortable couch to relax, and a bathroom with shower and toilets.

The apartment is located a bit far from the city center, which mean you will have to take the subway (with a 10-min walk), a bike or to walk (about 30 minutes) if you want to reach it.
The good thing in it is that the apartment is in a very quiet neighbourood, with a big park just nearby and some useful shops around.

And last but not least, Simon and Rasmus are really nice guys, easy to talk with, and you quickly feel comfortable in their place. They have a lot of good advice in order to discover the city. All in all, a nice stay!