Yea, but T6 has been proven by OTR truckers as an extremely reliable oil. Can Amsoil claim the same?
And OTR have what size sumps and filters? Again Rotella is not a group 4 and sold at TSC, chinamart etc...Why do you think all use it?
Amsoil is more $$$ since in the end it will perform better. Sorry I know many truckers down south and oil is a cult.
T6 is good oil but there is better. If you like it great...Some other might now and for good reasons.