i think you're getting mad after a very trivial question...
both Alnico and Ceramic Nailbombs are excellent pickups for either lead and rhythm work... the Alnico NB is tight and aggressive enough to give you a perfectly suitable metal tone, and the Ceramic NB is great for solos as well... so it's up to you, if your playing is a bit more on the aggressive side the C-bomb could be the best choice, but you can't go wrong in either way.