Amsoil is a great choice. JASO-MA, and full synthetic. Never known them to make bad stuff.
You beat the Universal Average on wear. Keep doing what you're doing.
Could be fun to ride down the vegas strip or to Red Rock Canyon etc on a Spyder !
Amsoil showed to be pretty stout. That's good shear resistance. Amsoil cSt @100 c is 14.6 to start, the M1 4T is at 13.4. Factor that initial difference in and they are almost a dead heat for shear resistance. Otherwise, Amsoil has no problems holding its own even with a slightly longer run.
I'm about to pull the trigger on a 2019 Spyder F3-S SE6, so thought I'd do a search here on oils. The manual calls for 5w40 partial syn, and that viscosity is quite limited. I bought a bunch of M1 4t 10w40 and Quicksilver m/c 10w40 syn at Wally World when it was on clearance a few months back for my 800 Tiger. Also have 3 qts of Castrol Actevo 10w40 partial syn on hand. Nice to see it won't go to waste once the Tiger's gone. My only concern with 10w40 over 5w40 was possible sluggishness with the SE6 transmission. Here in WI, it might get ridden occasionally in the 30*'s, but not too often..