the closest you can get to strat quack from two humbuckers is running the two inner coils in parallel. this is one of the positions on the PRS rotary switch. depending on your pickups and/or amp settings, this combination can actually have lots of strat quack. another cool setting is the two outer coils in parallel--this has the slightly notched sound like the middle position of a tele. check out a wiring site like guitarnuts.com for wiring diagrams of how to wire those coil-split combinations.
as for kinds of pickups, if you want great single-coil sounds from split humbuckers, the best wasy to get that is to use humbuckers that are built like single-coils. single-coils use pole-piece magnets; normal humbuckers use steel poles and a large bar magnet underneath both coils. Rio Grande makes their humbuckers with pole-piece magnets, like single-coils, so when those humbuckers are split, they are exactly the same as a single-coil. they're expensive, but if they sound as good as their single-coils that i own, they will be awesome.
Thanks scott from _actual time_, that was really, really helpful