Do I need F-spaced pickups or regular?

I have an epiphone g-400 and want to replace the alnico humbuckers with dimarzio super distortion pickups. and when you buy them do they come one at a time or both. because its like 60 bucks now and I want both pickups to be the same. but if I do that will it make it so I have the same tone twice, or will the position change that?