Before the amsoil I had Mobil 1 in it
I had the amsoil put in with a clutch replacement due to a bad TOB
I drove around 15000 miles including cross country with the amsoil in it and having to rev match to pass on the highway when I wanted to downshift to 4th, some days I had issues with all gears some time had issues going 3rdto 4th but the one that never failed was the 5th to 4th shift
The fixed worked great, I can slam gears all day long even drove back to arizona from Connecticut with the fix and I made it and nothing has fallen apart or broken yet. So far about 6-7000 miles with the current concoction.