The only difference between the OEM and aftermarket is that when you get your fork aftermarket it comes in a Fox box with a star nut. They used to come with extra springs in 04 and older, but I got my aftermaker 05 Vanilla and it came with just a starnut and a manual. OEM is just a fork (and a manual if you're lucky). Really little difference. Aftermarket Floats come with a pump as do rear shocks. Internals are identical as I've owned both. It also makes no sense from company's perspective to be making two different types of parts for the same fork. This is the reason why Floats, Talases and Vanillas differ only in what's in the left leg. RLTs and Xs have a bit of material shaved aroud the crown and have different steerers, but that's it.
_MK