I think it also depends on the lug nut hole of the specific aftermarket wheels you put on...(different wheel brands/designs may need different lug nuts depending on how the lug seats in the wheel itself)...this is all just a guess!
I could take a lug nut off my current 18's and see what they look like...
To add slightly, the stock nuts have a 60 degree seat, which is what 90% of alloy wheels use. When ordering nuts they may or may not ask about the seat although most default to an 'acorn' or 60 degree unless specified.
When I ordered my black set I needed to specify "M12x1.5, 60 degree". When rim shopping they'll typically say if they do not accept a 60 degree seat so watch the product info or ask whoever you order from. If something specifies 'tuner lugs' then they are a M12x1.5 60 deg, but they are the lower profile 'splined' style.