Mobil1 is far from the ONLY one... if it's the one you like, then that's fine it will perform well, but there are "better" oils out there for the same price.
Take advice from Oilman/Opie Oils, they will be happy to sell you whatever you want, including Mobil and Castrol, but they will also offer first class professional advice for your particular application and usage style and recommend the best oil available in each case - but ultimately they will be happy to sell you anything you wish