I've decided to make Castrol Magnatec my new oil of choice. Its main selling point is that it clings to metal after the engine shuts down, so it protects the car better on startup. And we all know that >50% of wear occurs on startup. Plus, it's cheap! for a full synthetic. $5/qt from Amazon plus free shipping.
I do wonder if the start-up protection is just a marketing line and if there's any truth to it. However, there are some reviews here that talk about it climbing the dipstick in a unique way. So maybe there's something to it.
Castrol Magnatec Reviews - ProductReview.com.au
I know it's decent, at least, because it's Dexos certified. That means it can be used in any GM engine, including turbo'd and supercharged Vette engines. And the FAQ:
Frequently asked questions about Castrol Magnatec | Castrol Magnatec
Eventually I'll get a used oil analysis done, and then I'll know for sure.