[Fordfan45]

So i just purchased a 06 f350 and i am looking to upgrade my motor but doing that i do know I need to replace headstuds. I also want to purchase egr delete kit. But i heard talk about replacing the oil cooler, and i was looking around and people were just replacing with OEM parts, why is that? Shouldn't you run upgraded coolers?
I was thinking of running ARP Headstuds, any advice on certain brands?