We visited Copenhagen during the Christmas time and had a wonderful stay in Mette/Leo's appartment for six days. They were very service-minded prior to the stay and with useful and responsive answers to any questions. The check-in went very well. The appartment is spacious and well equipped and we felt "at home" immediately. The Wi-fi was excellent. The neighbourhood was surprisingly quiet, being in so central, with grocery store just "around the corner". The access to Østerbro station is ok, but we choose to order taxi that drove us to "inner city" for less than 100 DKK. A large garden area a few blocks away provided an excellent opportunity for walking and jogging.
So, Copenhagen is a great city to visit, and a stay at Mette/Leo's appartment is highly recommended.