Synthetic oil

One thing I like about synthetics is that if you run a multiple weight oil like 10w30 the synthetic starts out as 30 weight and the additive package reduces it to 10 weight when cold. With mineral oil the oil starts out as 10 weight and the additive package brings it up to 30 weight when hot. So if for whatever reason the additive package starts breaking down you'll still have 30 weight with the synthetic.