ok im tryin 2 decide bewteen

2 dimarzio evolutions and a YJM single coil

a super distortion a YJM single coil and a neck evolution pick up

the single coil again and 2 seymour duncan invader pickups
the single coil is pretty low output and would make all the positions its active in lower volume than just any of the humbuckers by themselves but might sound good. the invaders are poop unless youre an image only guy and id stay away from those and go active if youre willing to sacrifice good cleans and tonal character for pushing through huge distortion. the super distortion is nice for a bridge pup and about the evo try one before you buy. theyre super sensitive to high harmonics and so sensitive that they can make sloppy hands sound way worse than they are. also check out the humbucker from hell for neck and tone zone for the bridge. both by dimarzio. thats what i would get personally. and the middle pickup doesnt really matter as much as the other two. you might be able to save a little by trying out just replacing the two humbuckers first.
what kind of music do you play, what guitar is it, and what amp do you have?