I went here for a Calexico gig and I have to say, it's pretty nice. In fact, for a gig, it's quite…read moreposh. It's a modern building, with a bar on the corner. There's an underground car park nearby that's open 24/7. Inside the actual theatre there's a cloakroom and more importantly a good sound system and it's not too large (max capacity 800). There is also a small seated area upstairs. But
... they have such a strange layout in the main hall. There are huge pillars, you really don't want to get stuck behind, and I don't know how to describe the thing they built towards the back of the room, sort of a raised standing area, which was such a waste of space. On their website they say they can raise various platforms in any desired position, but I would really question the point of raising such a thing during a pop concert, slap bang in the middle of the entrance.
The other bad point was the bar in the venue. The place was packed, the temperature must have been about 130°, but they only had one small bar open, and whilst the people serving did their best, I for one would have had more than one beer if I hadn't had to queue round the block for it.
That said, I'm going back for an Elbow concert when I'm back in D next month, so it can't be that bad.
Just an additional point, at the Elbow gig we went into the bar next door. Really nice food and good service. It's a modern, bistro style place, but serves traditional food like Handkase mit musik (ugh, but that's just my personal taste), very nice Zwiebelkuchen onion tart, and the best Kartofelpuffer I've ever had in Germany. So I've added another star. :)