Both of my cars use Mobil 1 Synthetic - for different reasons.
My 3.0L Mercedes V6 calls for Mobil 1 0w-40 and a fleece filter I get from Mann or the dealer. Granted - it takes 8.5 quarts and only requires changing every 13,000 miles.
My Lexus RX 3.3L V6 has 120,000 miles on it and I have started putting Mobil 1 High Mileage (5w-30) in it every 5,000 miles. Only 5 Quarts for that one. I started using the Mobil 1 Synthetic after having it in my other car. I'm not as picky with the filter in this one - I have used the Toyota filter from the dealership and the one in there now is a Fram from WalMart.