This was how we went with it:
When I first plugged in the guitar after installing this beauty, I hit my test chord - a clanging open D - and was a little puzzled to find that the sound had cleaned up a tiny bit, rather than gone more Steve Jones! I tried the higher gain settings on the JVM and found that the new pickup sang like crazy compared to the BK, with controllable feedback blossoming easily. The notes were still very distinct with good pick attack. This was a real head-scratcher for me.The Riff Raffs come in at about 8.2K and the coils are spun with only about a 10% bias (more copper one coil than another).
To get a slightly a wee bit more crunch without going muddy like the LB's etc.. you would increase the bias to around 15%, scatter wind the bobbins a bit more and push the output a little, say 8.8k to 9.1k. That would make the pickup hotter without losing any of the clarity and middle punch and it would start to break up a little more at lower gains. The only downside would be that if you wanted to split the coil you would have a rather spanky single coil tone. Not a problem for you I would have thought in this instance. It would also not outpower the B90 to any greater degree.
Yesterday I recorded my first tracks with the pickup (see the Jazz Noir thread in the Listening Booth) and both characters of the thing can be heard. My conclusion is that the pickup IS hotter but it has such unbelievable clarity at ordinary crunch gains that it SEEMS less hot. Having recorded the thing I'm absolutely stoked. Ok, it didn't exactly replicate what I originally had in mind but at that time I was thinking more towards what I thought I needed for the Shambollix live stuff. It could still do that job, but what I have in my hands is a complete gem of a pickup that I didn't expect to get.
Thanks, Mutt - it's a fucking belter.