This is my situation only, so it may not be relevant for others...
I occasionally track my car, drive spirited (think Dragon) and use as a DD during the Summer months. I have never experienced oil temps high enough to go into "limp mode", so I do not have any type of oil cooler. However, with that being said, I am still thinking about putting in at least a 24-row, mostly as an insurance policy in the event I ever run into conditions that MAY raise the oil temps to unhealthy heights.
Better to have and not need than need and not have...just my $.02
As-far-as adding mods like mine (CAI, CBE, HFC, tune), I think the car actually runs cooler because it is now more efficient and does not have to work as hard...