My stuff isn't anything special, but my daily drivers have all made it over 200k, and an old truck that ran to almost 300k before selling, and i've been using NAPA Full Synthetic for the past 8-10 years. Before that, i just used NAPA Conventional. Which NAPA is the same thing as Valvoline... Maybe it is good marketing, but the NAPA guys do say there are extra additives in the Valvoline High Mileage Full Synthetic. Plus i use the Platinum filter. And i buy in bulk, when on sale, which is about every other month.
On a side note, multiple people have told me to try Amco? I think that is the name. Apparently that is the "good" stuff? But also expensive? The first time a person contacted me about the stuff, was on a Jeep forum when i was looking for stuff for axle gears. I was thinking of trying it in my 2 cycle engines first, as they STINK when they run right now.... Yes, I know different types of the stuff for gearing vs engine oil. haha