I run Mobil oil in my street cars and my race cars - specifically Mobil 1 synthetic.
Haven't yanked any of my street cars apart to check on their progess, but I have a 10 year old V8 Tundra that started getting Mobil 1 at 1500 miles and still runs like a top (145k miles, no smoke, easy starts, no valve chatter).
As for my race cars, I tear those engines down routinely, and can say that synthetic is much easier on the parts. I used to run Texaco Havoline dino oil (my old sponsor sold their products) and had several oil related breakdowns in one season. Since switching my late model (358 cid, 2 bbl carb) to Mobil 1 about 8 years ago, no breakdowns or any oil related problems at all. Can run 5-6 races (250-350 VERY HARD miles) on the same oil and it comes out nearly as clean as it goes in. My new sponsor (for the past 4 years) is a local tire company that sells Mobil 1, so I don't have to put Mobil 1 into empty Havoline bottles anymore...lol (Havoline use to burn out a lot (usually took a quart between heats), so I took some to the track with me a lot...before I changed sponsors, I changed oil brands, and was putting Mobil 1 into Havoline bottles to hide the fact from my sponsor - not that Mobil 1 burns out like dino oil did...sort of like Hendrick Motorsports puts Mobil 1 into their Quaker State bottles today since they too run Mobil 1 but can't admit to it.)
I tend to change my street car oil at 6k miles (regardless of whether their "computers" tell me to or not) since that is about the right time to rotate the tires. I simply do both at the same time. My GMs all want me to go to 15k miles between changes...according to their oil life monitoring systems...but I never have. Yes, I started my '08 Runner on Mobil 1 when I thought she was ready for it (about 3500 miles - to seat the rings properly and whatnot).