Seems Mobil 1 is a favorite around here, along with Amsoil and maybe Redline, since they're the only true group IV oils now. I'm just looking for the least expensive group IV oil, which apparently is Mobil 1. So where do you get your Mobil 1 fix? I read that Walmart has them in the 5-qt jugs for pretty cheap. Do they go on sale cheaper elsewhere? Or is this a taboo subject around here, based on the lack of hits from my search.