Never seriously had one in one of my old guitars and I didn't get the hype from trying them in shops. Thought it was an "old men being old men" kind of thing. Nope. Pretty fucking killer and hairy sounding. So now the question is whether to buy the hype further,
a)Are the 80s ones really better?
b)Is the Warren Demartini CS one (which is supposedly similar to an 80s JB) as good as I've heard?
I'm not sure about "better", but I had an 80's MJ JB in my Charvel Model 6 that I replaced with a Distortion, and I really liked it.
I've still got it lying around somewhere, and I've been thinking of a project guitar to put it in.