I played the Fiddlers Elbow a few years ago.
We had an excellent sound engineer, but I think the promotor was a bit flaky and all the othe bands pulled out. Since this is the only time I've ever been there, I'd take it with a pinch of salt.
House engineer: Excellent
Typical audience numbers: We played to our mates and the local drunkards!
Quality of billing: Terrible, all the other bands pulled out!
Vibe: Acceptable
Stage sound/monitor mixes: Excellent
House backline quality: Not sure, we used our own.
Tricks to get industry people down there : Trendy haircuts, tight jeans and don't tune your instruments!