For me, Oil is cheap & filters are cheap. I've gone from "whatever's on sale" to Amsoil back to whatever's on sale & back to Amsoil again. This time I used a cheap filter & regular oil for the "rinse" and followed it with Amsoil & one of their filters for the long haul. As a mechanical engineer, I do have to wonder what makes these synthetics so good compared to "regular" oil, but my son (who was helping me) sells it, so...