I use the bristol on really light tackle but won't use it for heavier applications. The knot works fine if you use soft leader material and wet it. The knot really needs to bite it for it to work properly. As Warwick said, don't use it with fluoro as that is just asking for trouble.
It's a knot that may look easy to tie but there is a very, very fine line between between perfection and disaster with this knot.
From my understanding, it is the same knot as the Cairns quickie.