^^I would of guessed you double gasketed the filter rather than no gasket at all. Back in HS, a student got an ear full of all sorts of choice words from the instructor when doing this. Ironically, the instructor had touched on this topic in a previous lecture.
Anyways, my method of preventing any gasket issues is to make sure the new filter is always right side up. From the time it comes out of the box to the time it gets installed.
As for mobil1, ymmv. I had a bad experience with it in my camaro. By 80K miles, the car had excessive oil consumption (1qt/400-500miles). A friend running this in his dodge truck also noticed considerably higher consumption at 60-70K miles. Engine defects, perhaps, but it left a bad taste for the oil
