Stayed here for two nights this week. Had previously stayed in one of H'Otellos a couple of times but very sterile. Pictures on line looked more appealing from Das Nikolai's website and so it turned out to be.
Reception was friendly and efficient. I actually arrived about midnight first evening and was greeted easily and given key with absolute minimum fuss.
Room (102) not huge, but a bit of individuality with lamps and chest of drawers. Will be interesting to see some other rooms over time. Free wifi. Room faced out onto street but was still pretty quiet in evening.
Breakfast room nice and really good selection with fresh cooked egg dishes available (and with smoked salmon was a real treat). Everyone there spoke English well (and friendly).
Easy walk to main drag and loads of bars / restaurants.
Only minor gripes were the usual German issue of offering 2 single duvets on a double bed. Also slightly odd that wc is behind only a partial door rather than fully shut off. OK for me as I was on my own, but might be slightly odd if together.
For me, a decent place and will look forward to another return as in Munich maybe 2-3 times a year.