warpigs normally are made with a 2 row of allen or screws, a "pair" of the same type open or covered. You can always ask Tim for a special personalized pickup. (like 1 row of allen and another row of screws for example)
I have a Warpig in raw nickel with standard polepieces and it is still a monster pickup. Tim didn't say anything about the tone being affected when we were discussing the pickup. BK's pole screws are all mild steel and I think that because of this there will not be that much difference.