Castrol synthetic or Valvoline?

Hey Trailbeast,

Did you see the thread where there was a link to a very interesting oil test results site? It's called 540 RAT tech facts. A lot of reading but very worth it.

Ok, maybe not quite the answer you are looking for but I hope it helps;
After reading it, I decided to try out the 5w30 Quaker State Ultimate Durability in the gold bottle. As soon as it stops raining here for long enough for the pavement to dry out, I'm gonna change my oil and try it for a few months, then I am going to give the 5W20 Valvoline MaxLife High Mileage, API SN, dexos 1 approved, synthetic blend (red bottle) a try for a few months. I don't really care about brands so much as I care about hard data.