Mobile 1 is definitely good stuff -it score very, very high on most tests that it's subjected to and proves to be a superior product without doubt.
However, Amsoil and Amsoil products are rated even higher in most lab tests.
The only problem with it is, that it's difficult find and it's expensive; like $6.00 a quart expensive...

I've alway's Castrol GTX 10W30 dino and never had any problems (and we get some extreme temp fluctuations throughout the year in NE Ohio -hehe, ask brat4by4.
In any event, you could probably put coffee grounds in your car as long as you changed it soon enough. The thing about oil is that most are comparable in terms performance and wear resistance for the first 3k miles. It's only after the thermal breakdown period begins that you start to realize how well the quality brands are engineered, and how differently they're formulated than inexpensive brands.