Well reading all of this really makes me upset. I started with dino oil for my break in period. Directly after I switched to mobil 1 full synthetic 5w30. I ran It till just under 15000 miles then I took to the subaru dealership in grand junction colorado, where they put dino oil back in against my request specifically for mobile 1 synthetic. Now at about 19600 miles, I am having an oil consumption problem, and I just had them switch back over to synthetic this change. Is it a strong possibility that the switching is what is causing my consumption problem (Not leaking, I checked my heads and there is no sign of oil leakage. Also, How low does the oil have to get before damage is done to the engine. When I checked my oil before my last change, it was off the end of the dipstick, I added a full quart to bring it back up to full. Heads are about to roll at whites mountain motors, this is the second subaru that they have serously screwed up. Thanks for any input.