Premixed Antifreeze brand?

[dghii]

I don't know of any thats already mixed that won't open up a discussion about the evils of non-OEM coolant.
The Porsche coolant is about $30/gallon undiluted. You can buy some and cut it 50/50yourself with distilled water. A little cheaper solution that will work is Zerex extended life GL-5 IIRC. You can find it at Pep Boys and it, like the Porsche stuff, is not diluted. I think there's Pentifrost product but I don't know anything about it.