I ran it a few years in a '02 ZL 600 EFI and a '02 Renegade 700. First, both sleds smoked really bad when I used it. In fact, I turned the Renegade's oil ratio to 80:1 just to make it bearable. Second, I was always scratching carbon off the power valves of both sleds with a knife. I usually had to pry the valves out because the carbon was so bad. Third, it burned my nose and eyes (nose ran and eyes watered). Fourth, I was always last in the group because no one else could stand the smoke the sleds where producing.
I switched brands and the sleds where better. The smoke was significantly less. There was never hard carbon deposits on the valve where I had to use a knife to scratch it off. Usually wiped off with a rag dipped in cleaning solvent. My eyes and nose didn't burn. And the group never forced me to the end of the pack.
Now, all my sleds are 4s because my eyes and nose are burned out by 2s oil. When I ride with 2s, their always behind me.
That was my experience with Amsoil on two separate sleds built by two different manufacturers.