I'm always up for getting the most bang for my buck. We ate at Biergarten for the first time on our recent trip (Candlelight Processional package). We loved it. The food was yummy, the atmosphere is awesome, the entertainment was great, our table mates were nice, and our server was fantastic...very personable and attentive.
I was honestly a little worried about it, but it was a pleasant surprise. We went at dinner in December, but I'd think a lunch during a summer day would be a nice respite from the heat. And I'm always a fan of (good) buffets with lots of variety. There is something for everyone and whatever mood you're in on that buffet. Plus you get a show!