I went here with a German friend who makes special trips here a few times a year (2 hours from…read morehome) to stock up on mustard. Yes, mustard! Senf, in case you didn't know, is the German for mustard.
The shop is amazing and does have many different types of mustard. You can sample them as well and I did, and decided on the beer mustard. The one with the orange flavor was also excellent. There are just so many different ones.
They also sell other German products including wine, sausages, pates, and so on. The jarred fruits were also very good. If you're stuck for a present for somebody, they also do gift baskets. I wouldn't mind getting one from Santa Claus!