I'm running castrol 20w50 at the moment. I haven't been driving everyday and only have about 300 miles on this oil but I'll be switching to mobile 10w30 one day next week. As far as the oil is concerned, I haven't had any problems out of it... but I haven't given it a real chance yet either.
I CONTRIBUTED TO THE WIKI! ah... turbo. I love the turbo, the boost, the speed, the sound. and its all better when you do it yourself. cheaper too.