I stayed at Karl's place for 3 nights and it was everything that we needed. It comfortably fit 4 of us and we were happy with the amount of space that we had while we were all in the apartment. Karl was helpful and quick to respond, the apartment was very clean and all the photos are extremely accurate. The beds (daybeds I guess technically) as well as the pull-out mattresses were all comfortable and there was enough blankets and pillows to go around.
The only downsides I see are the location which can be a bit of a trek to the closest Metro station (especially on weekends when the closest station isn't in operation) and when we got there, there wasn't any shampoo in the bathroom (though there were 4 conditioners funnily enough), but I'm sure that isn't an issue most people would run into here.
Overall a great value and very accurate listing. Karl was great to deal with and I have no reservations in recommending the place.