And thanks for replying YR. If my oil temps dropped 15 degrees, it would be good in one way, but then I'd ask myself where was that heat going now!?! LOL I tend to be a believer in using the oil as another way to carry heat out (as long as the peak temps stay in control). Again, my choice because in rally, you are running large sump protector to protect the engine and trannie, and with that and a stock engine compartment, you are REALLY challenged to get heat out when you are hammering on the engine for up 30-45 minutes at a time. (The same thinking applies in favor of lighter oils; better heat flow out of the engine to a cooler.)
I know this seems like a digression, but what I am trying to show (in a poor way, no doubt) that a benefit may not be perceived in exactly the same way in another application. If the reasons to do something are known, then better decisions can be made per application. I tend try to always ask what people are going to use their engine for before answering a lot of threads; others do the same when they ask about budgets.