I'm considering a custom bike build but can't make sense of the bottom bracket situation. I understand the different types but can't work out if the crank arms are compatible with all BB30 and PF30's? Reason I ask is I can't find a PF30 specific crank. All cranks seem to be BB or GXP (I figure the GXP needs a GXP BB).

I won't be putting the BB in myself but still need to know which cranks to buy... If I can get a custom build within budget (which is gonna be hard).