I don't know that Amsoil is really all that much better than it was ten year ago. But when your Competition like Mobil raises the price of their flagship oil from like $30 to the nearly $50 price for their AP you have some room to capture some more profit.
2004 Toyota Corolla 121478
Out: QSUD 5W-30 Purolator One 5030
In: Valvoline ML 5w-30 TG4967 117530 2-8-18
2006 Duramax 74016
Out: T6 5W-40 M1-303
In: T6 5W-40 XG9100 73752 4-22-18