Had a great time in Copenhagen. Mathiaes is a superb host, very responsive and helpful. His apartment is in a great location and well equipped, with plenty of towels, toiletries and even toothbrushes! Although it can get a bit noisy late at night / early morning it didn't really bother my wife and I (it might bother some though). The location far outweighed the inconvenience of the noise. It's a stones throw from Tivoli, Kongens Have, the (very) little mermaid, Nyhavn etc. Perfect.
The check-in and out was also seamless.
All round, I'd thoroughly recommend Mathiaes' place if you're heading to Copenhagen for a short city break.