Positives - lots of them - perfect location for Friedrichshain-Kreuzberg area, on a quiet and safe street. Apartment is very smart and modern, just as in the photos and the description, with outside space a definite bonus. Everything high quality and worked perfectly. I guess when you read about 'gentrification' in this part of Berlin, they are talking about places like this, which did make me think a bit.
(Small) negative - no doubt the apartment is perfect for a couple but the sofa bed might not work for all groups of four. It's quite small and there were no sheets provided (unlike other places we've stayed with sofa beds). Just a duvet and a pillow each. My teenage boys got by with it (teenagers often sleep on sofas!) but I'm not sure all adults would have been that comfortable.