After spending 2 week in a backpacker hostel, I chose a room at the Derag for my last weekend in Germany. I had been swayed by the pictures of the establishment, its fair price, and its sauna installations. Upon arrival, staff were very nice and I had a quick check in. The room was okay; nothing more. It was clean, sound-proof and the 2 free beers a day were a nice touch.
Unfortunately, my room on the second floor lay in full sun, which made the room very hot upon my return every evening (I did not leave the curtains open, but they were opened during the cleaning). There was no AC: There was a wall control hidden in one corner, but it didn't seem to be working. So my stay was very hot and stuffy, which made it difficult to sleep (opening the window was my only option for the night, which also let in much noise from the busy street below). A second criticism would be the shower. Though the size of the bath was amazing for relaxing, the non-movable shower head fixed to the corner made showers an uncomfortable gymnastic exercise.
One of the reasons I picked this hotel was for its relaxation installations. If, like me, this is a deciding factor for you, consider other hotels. The first night of my stay, I headed down to the basement sauna area, but was quickly turned around by a very rowdy group of naked German men. On my second and third nights, the sauna was closed for maintenance.
Overall, my stay was good. But the reasons why I picked this hotel were disapointments.