Is there any difference in formulation between the Quicksilver and Mercury branded oil? I've seen both on the shelf next to each other and the Mercury branded stuff cost more. Is one straight dino oil and the other a synthetic blend? And is it safe to mix the two if needed? I do know for certain brands different formulations of the same brand of oil won't play nice with each other.
I remember reading that both of the Mercury branded oils (Merc and Quicksilver) are fine for my 75hp Merc 4-stroke as long as proper weight is used. Really just wondering if one is better than the other?