Yes, my metal band played there last summer with Godsized. It's run by a biker group and has an eight-bed dormitory in the back.
It was a four or five band line-up. The PA was huge and sounded good, the sound guy seemed to know what he was doing but the stage was raised and boomy.
It was packed but we didn't go down too well, if I recall. Godsized fared better but they headlined.
Afterwards, the bikers looked after us very well. We partied with them until about 5am. They were great guys.
It's worth going for the experience but, as you say, the money doesn't really make it worthwhile. To top it off, I got a speeding ticket on the way home -- watch that stretch of the M180 for cameras and coppers.
Cheers
Mark