I do believe that Amsoil is a very good oil but I also think it is over-hyped and overly expensive. I used to drink the Amsoil Kool-Aid many years ago and then determined that $23 for a 5 quart jug of Pennzoil Platinum at Walmart would have the same effect on my engine. They do have great marketing and the product is very good indeed. However, I do think it was way over priced based on the other excellent oil choices on the market today. To be fair, I haven't priced Amsoil in quite sometime so just guessing that it is still overly expensive as compared to PP, Mobil1, Valvoline and Castrol.