The Paulaner one does allow walk-ins, but the tables are reserved. Its in the mansion house. There was a german band alternating with a DJ early on before the real German cheese DJ came on. Loads of hand slapping and drinking songs. I had a good laugh at it anyway.
They have the Oktoberfest on tap and the darker weiss beer. The rest of the range are in bottles behind the bar.
The Oktoberfest is available in the porterhouses and a few other bars as well.