Hi, your thread caught my eye because I'm a big fan of LP Juniors and Specials, but I'm afraid I haven't tried any of the new BKP P-90 range.
The description of the Half Note does seem to emphasise the pure, natural tone and that it's mainly for jazz and other clean styles - nothing to suggest it's suited to anything heavier. Whereas the Nantucket seems to be designed more for the full range of classic P-90 tones.
If I was buying for my own guitar, I would certainly like to try the Nantucket bridge. On an LP Special, I'd also be interested in the Blue (rather than Half) Note as a neck pickup for a softer, sweeter kind of tone. But I do like a lot of contrast between neck and bridge, more than most people seem to.
So, I reckon Nantuckets are probably going to suit you better - but hopefully someone who's actually tried them will chime in.