I just took mine off yesterday because I am one of those 'I hate clutter' type of guys. I beat the sh!t out of the car just before pulling it into the driveway and let it sit while the dual fans ran through a cycle and the I shut her off. Not exactly scientific, but right after I shut her off, I grabbed the oil filter to see how hot things felt and I could grasp the filter for about 2-3 seconds before I had to let go. Didn't exactly feel like things were coking up in there.
With a 160* stat, f-body radiator and dual fans, I've never seen coolant temps over 169 even on a 95+ degree humid day down here in FL.
Since we're on the subject, if anyone wants the oil cooler, I left the lines attached so it would be a plug-n-play set up for $50. If you want pics, I did the F-body radiator swap write up that is found on turbobuicks.com and gnttype.org. It's the exact same cooler and lines as in the photos. Got about 10k miles on it since the install.