The stores mentioned could carry AMSOIL if they wanted to abide by AMSOIL's Policies but they don't want to... They have the Wal-Mart Mentality... We have the this is the way we do it if you want it mentality and it is not negotiable...
As far as local..... go to
AMSOIL - Synthetic Oil, Motor and Engine Oil, Lubricants, Air Filters, Oil Filters and Greases and do a search for a local dealer... It will not give Retail Accounts...
As far as Warranty... It is against the law for the OEM to void a Warranty due to maintenance practices or products used as long as they meet or exceed OEM Specs. The Specs for tranny fluid on the Manual Honda's is so loose you can run just about anything in them.
Also, Don't let a Dealer BS you... A Dealer DOES NOT have the power to void a Warranty for ANY reason. It must be done by an OEM Rep.
Doc