Just go to your local Walmart and get some Penzoil Synthetic. They often have the 4.4L jug on sale -just keep an eye on it and then stock up.
I'm skeptical about running those brands...after a bit of research they didnt seem to fair to well in the tests being proformed (although I am sure the tests are biased)...I rather run just amsoil...seems to be preferred by many...I actually originally wanted to run royal purple, but doesnt look like that fairs to well either...
I have run Amsoil in the past and was happy with it.
I tried Royal Purple and wasn't. I have since switched back to Mobil 1 and since it's changed every 5k's I think it should be fine.
However every mechanic I have spoken to has told me that as long as the oil is changed religiously conventional is fine for most applications.
__________________ 2001 NBM Z/28 Convertible LS1- LS7 clutch, Tick M/C, S60, 4.10
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I just don't Know
Oil is one of those things that everyone has a different opinion on. But rarely do you hear a really good logical explanation as to why. The Bob's site has some good info.
I would skip the Synthetic and go with regular oil if you change it regularily. Lighter oils lubricate better than thick (I use 5W30). And stick to a common brand like Valvoline or Castrol. That way you can always run the same oil, year after year without having to look too hard to find it.