I don't know its effects having not tried it but here are my thoughts-
I'm fairly sure the best oils already have either moly' or additives that are equivelant to it. Oil companies, such as Amsoil and Mobil 1 have larger budgets and study oil all day, every day, and the oil they sell is as good as its going to get already.
Also, oil can be tested for wear resistance properties. You could buy your favorite oil and send out 2 batches to an oil testing company, 1 with mugen additive and 1 without. However, at $25 dollars of this stuff per oil change, I would just stick to a good oil like Amsoil.