Amazingly enough, the JB is the one constant I had when two/three years back I was in my heavy gear-searching mode.
As stated above, it ROCKED in some, it was bland in others and straight forward wrong in a few.
However, it fits my Washburn MG-122 SO well (the only JB-equipped guitar I own) that I can't imagine changing one thing about it (while in her).
The only problem I perceive about the JB is that by being the most widely recognized and thus used pickup, possibly in the world, it has become somewhat of a panacea.
That is, it's the one pickup people expect to solve every and all problems they might be having with their guitar.
NO pickup will do that and the JB is no exception.
BTW, the option I chose was "Yes. But, I'm more likely to use something else." because truth be told, my tastes go a tad higher-gain and a bit more balanced EQ-wise (but still with enough mids to cut through the mix).