We saw BH at the Golden Horseshoe last summer. I had been to DL 20 times too, and had never set foot in the GH. I didn't even know about the BH show.
There are three BH groups, Gold, Blue and Green. Supposedly the Gold and Blue ones are better than the Green. We saw the Billy Gold. Here is a link with more info:
http://www.ladydisneyland.com/pictures.html
And here is another link:
http://www.jansworld.net/billy_hill/1_billy_hill_main_page.htm
So we showed up 45 minutes early for the 5:30 show, and were the 4th group in line. We got a table right in front.
From what I had read on the DL forums, our expectations were high. That might have been our downfall, because we did not think the show was
that great. We are a musical family and appreciate their style of music. We might go see them again in the future, but it would not be a priority.
I am not saying they were bad, we just were expecting more, I guess. It was fun, and if you have lots of time, go see them. For lots of people BH is their DL highlight. We won't next time unless we run out of other things to do.