It's great! I have it in my truck. I ran it in my Corvette 1st about 10 months ago. I get mine from a "speed shop" in tampa. NAPA here only carry's Royal purple and Mobil 1. I've used them all. I actually broke a Rocker Arm on my Vette using Royal purple...not sure who's to blame... but different issue..that's why I switched to AmsOil 10W40. I'd have to say AmsOIl is GREEEAAATTTT!!!! My 94 4runner with 3" BL, 35x12.50 Mud Rovers on 15x10 steel wheels, stock 4.56 gears 5spd, exhaust, intake no emissions and some doo dads gets AMAZING GAS MILEAGE!! I haven't calculated it do a .x yet, but roughly 18-20mpg overall...at least. I don't think i'm ever switching oil. I plan on running it in my Turbo Supra when the engine is broken in, which is a drag car:) AMSOIL 10W-40 & Toyota Filter. Can't beat it.