Not sure why it is good, just feels good versus the Motul Gear 300 and LubroMoly that I had been running in the past, and a lot quieter. In theory another high-solids oil like Shockproof should behave the same.
Amsoil's test that they flaunt shows the least amount of corrosion to these metals over two handfulls of other brands, so I figured why not go for it.
I was actually considering the Wal-Mart brand oil as mentioned many times by mikeythejew, but the Amsoil guy was closer and I actually had some cash on me, so decided to risk it.