Great point with the use of TCW3 in air cooled OPE, never thought about that, I guess I had better get it outta my saw and Echo trimmer!
I've became really fond of the Amsoil Sabre oil, local saw shop sells it in a large "ketchup" pack that you add to 1 gallon of gas, its cheap and runs great in everything I have so I guess I'm going back to it.
In my karting days our KT100s ran great on Klotz Beanol and supertechniplate oils. We also ran some komets and parillas and never lost a motor due to lubrication.