Since you asked, I prefer Castrol.
But it's hard to go wrong with oil these days if you stick with a name brand.
Apparently even Pennzoil has good stuff now, their Platinum full synthetic is getting rave reviews as the top synthetic, and at a great price. Mobil 1 continues to be good, as does the Castrol Edge line.
For regular oil, Castrol GTX and Mobil 5000 are excellent choices.
Motorcraft semi-synthetic is also really good stuff, and often costs less than regular oil, especially if you can find it in the correct viscosity in the 5-quart jugs.
Be sure to use a good filter too...not FRAM. Motorcraft FL-1A is a Purolator PureOne at a lower price.