8-3/4 Vs Dana60 Vs 9" Rear
There is no mistaken that the aftermarket 9" stuff is killer stuff. Both the aftermarket 9" and the Dana 60 is probably a draw in the strength department. So it would come down to if you wanted to be able to change gears easily. If you decide to go 9" and you thought about getting a third member for racing and one for street cruising I would get the custom one for racing and run a stock type pumpkin for cruising that way it would save you some money.
Chuck