A tour guide we had earlier in the day recommended this place as a great restaurant serving traditional German food at a reasonable price. It certainly didn't disappoint.
We got there early (around 6pm - it was also a Monday) as we didn't have time to book and am glad we did. We were seated immediately (in saying that it was already busy) but by 6.30pm there was queue - everyone seemed to be seated quite quickly though.
German food was what we were after - pretzels, schnitzel, pork and beer - in a warm atmosphere. Some of the reviews said the service was bad and slow. We had neither. Staff were nice, attentive and everything came out quickly. We had read on TA it was like a German beer hall, which it was, but really slick and surprisingly quite a romantic atmosphere.
All in all, we paid 50 Euros for dinner including pretzels, a couple of drinks each, a main meal and a tip. We were happy with that. I would highly recommend!
This place is across the road from where the Christmas Markets will be held in the Gendarmenmarkt from next week so imagine it will be even busier then! Would definitely recommend a booking.