Zerex???

[Cloudsurfer]

The G-05 stuff is likely a better formulation than the others, and a lot of BMW guys (myself included) are running it with good success, but I'm not sure I'm ready to put it in the Porsche. I've been using the Havoline Dex-Cool in the Porsche.

There are two ways of looking at this. Considering how infrequently one swaps coolant, and how little the car takes, it's really a wash in overall cost to not just spring for the factory stuff. On the other hand, why pay over twice the price for the factory stuff, when equally good alternatives are available?

Honestly, I think that where all the coolants have gone in terms of development, you could probably buy the absolute cheapest, Walmart branded stuff and as long as you made sure (via a good flush) that you weren't mixing coolants, you would be just fine. I don't think you can even buy a coolant anymore that isn't Phosphate free.