Since you like the Duncan '59, I'd go with a Mule. I believe the Mule, like the '59, is modelled after the late 50's PAFs, so they should be somewhat similar, though the Mule will prove more organic and open sounding if my other Bareknuckles are anything to go by. I have used '59s and loved them, but I haven't used a Mule (though I intend to buy a set for my Eclipse shortly), so I'm speculating to an extent.
One word of caution borne of my experience, though. Keep in mind that the Nailbombs are pretty dark-sounding pickups, even in the bridge position (though less dark than in the neck). They do sound great and they'd definitely have the power to cover the heavier stuff you'll play, but I personally find it too dark for my tastes in a mahogany guitar. If your NT is one of the ash models, it might work better, but I still find the Nailbomb neck I have in my alder strat pretty dark. Again, having not used the Mules I can't say for sure, but I expect they'd be brighter than Nailbombs, and I would find it strange having a brighter pickup in the neck than the bridge.