May I please use this thread as a good opportunity to ask how you would describe the differences between old early Duncan JB, Custom & Distortion pickups?
I'm in the same boat as ChurchHill, been brainstorming pickup options for a special old 70's model V.
I think I'll keep the neck pickup vintage style (old PAT# / T-Top like), but been thinking about what to put in the bridge especially; looking for a classic hot-rodded PAF vibe to channel my inner late 70's -> 90's Schenker influences

I'd love to hear others' opinions on this, too, mostly because I'm a little outside the norm with JBs and Customs.
I've always found the JB to be too mid-focused for my tastes. I'm not a fan of the Celestion V30s for the same reason. I hear other people sounding great with them, but when I play them, it's like fingernails on a chalkboard. There have been exceptions with the V30s, but I've never found a JB that I've liked. The only one I haven't tried is the Custom Shop Concept set.
Now the odd thing about that is that the Distortion is supposed to be the same wind, just with ceramics instead of A5s. I've tried putting the ceramic from a Distortion into a JB and it did NOT sound the same, to me. I've tried putting the A5 from a JB into the Distortion and that didn't sound the same, either. So, I'm just not buying it, that they're the same, but maybe it was just the set I tried that with. I've also tried an A2 in a JB and it was almost worse. The A5 in the Distortion was better than the JB, but it was a little too soft in the low end, so I prefer the Distortion the way it is stock. Does this mean I won't like the RTM? I don't know, but I'm still interested in it. I think I would because there is another Duncan with A2s that I like.
Which leads me to the Custom Custom. I like it better than the Custom because it's not as sharp in the highs. The Custom is a great pickup in a darker guitar, but none of my Vs are dark. Then there's the Custom 5. Back before that was produced, I put an A5 from the JB I was talking about above into a Custom Custom and it sounded f'ing GREAT. So, cool, I thought, Duncans gonna make these and they'll be great, too. Um, not so fast. I tried one of the production Custom 5 and it was nothing at all like the one I made, it was harsh and scooped where mine was bright and full. So, IDK, not sure I buy that all the Custom variations are the same wind, either. Or maybe Duncan uses Oriented A5 in the new Custom 5s and Unoriented A5 in the JB, or the opposite of that, or different compositions, or what? IDK.
So, for me, the Distortion remains my favorite in darker guitars and the Custom Custom remains my favorite in brighter guitars. My Vs are somewhere between that, bright but not too bright, so the Distortion might be too much and the Custom Custom might not be enough.
FWIW, where I am right now is debating trying a Custombucker with and A4 that I got from Throbak. I was originally experimenting with those for an LP and the stock A3 is a little weak for me (still sounds good, though). Right now, I've got that pickup in an SG and it is just powerful sounding, like exactly what I think I'm looking for with the V. My other thought is the BKP Rebel Yell is possibly the best hot-rodded PAF sounding pickup I've got at the moment, but I like it where it is and don't want to get another set if I can find something new. I've got another set for the SG, and I've got some others in my parts drawer, including a J90C, BKP Abraxas, and a set of Throbak DT-102s that was ear-marked for an ES. Too many options, I know. If I was going to buy something, using a Distortion neck in the bridge, or better, finding an old Seymourizer II, is tempting.