I just love smacking conjecture and mythology in the face with true hard facts and real data.
Let's review the basic claims of synthetics being "better".
1) They give better "protection"; I presume this means lower wear.
2) They run "cleaner"
3) They flow "better"
4) They give "better" fuel economy
Let's start with the "better protection".
Please look at the two links I'll provide. You can read the posts if you choose, but it's the raw data in the UOAs I want you to look at. These are dealing with HDEOs, but the reality is there, if you're willing to open your mind and compare/contrast real information ...
This one is of a Dmax running 15w-40 Delvac conventional oil.
This one is of a Dmax running 5w-40 RTS.
OK - now look at the wear numbers and the OCI durations.
The first UOA report examples are at 7k and 9k miles. The wear metals are all really low, and only the Fe seems to be moving with the mileage exposure. It probably averages around 1.45ppm/1k miles. All other attributes were "normal" enough to not warrant discussion. Blackstone even suggests running up to 10k miles for the next OCI/UOA.
The second UOA examples are at 5k miles. The wear metals are all really low, and the Fe is a bit lower than the above example. However, on a wear/mile basis, this example of "synthetic" actually showed a slightly higher wear rate of Fe with 1.6ppm/1k miles. All other attriubutes were "normal" enough to not really warrant discussion. Oddly, Blackstone suggest sticking with the OCI/UOA plan at 5k miles.
So, we have a guy who runs dino 15w-40 in his Dmax, and actually gets a lower wear rate than the other guy with synthetic, regarding Fe. The Al, Cu, and Pb are all low enough that they just don't matter at all for the discussion. The insolubles are all good, the coolant is not an issue. The fuel was a bit higher in the synthetic lube vehicle, so that might have contributed a bit to the Fe, but the reality is that they were close enough to almost call them even.
Now, here's my point I've been banging on, some of you are ignoring continually. For moderate OCI durations, in non-extreme environments, just where is the synthetic "advantage"? These two engines are wearing about the same, even though they use different base stocks; one conventional and one synthetic.
Let's look at "cleanliness".
Synthetics run cleaner, some would say. But that is an over-rated and mis-understood concept. Base stocks don't clean engines; detergent packages do. It's the additives in oil that clean, not the oil itself. So, becasue synthetics are made to be run longer, they typically have more detergents in them. But if you already have a clean engine, and you OCI with moderation, the "dirtiness" of your oil and engine never get to a bad level in the first place. What good is tons of detergent if you dump it frequently? Having more cleaner than necessary is like me having way to much oil stashed in the garage; it makes me feel good, but I have no use for it because I can't use it all at once! Further, in both UOA vehicles, the insolubles (soot and oxidation byproducts) are pretty much the same. On top of that, detergents really only clean up what falls out of suspension. If your oil's dispersent package is working sell, there isn't much to "clean" because the anti-agglomerate additive should be doing it's job. The reality is that engine design and manufacture has much more to do with engine cleanliness than does lubricant base stock.
Let's look at "flow".
Two things affect flow; lubricity and viscosity. I'll agree that the base stock of synthetics might be a bit more "slippery" shall we say. But the grade of a dino compared to the grade of a synthetic is set by your choice of grade. Once up to temp, the viscosity of a "40" in one is about the same as a "40" in another. Truly synthetics do flow better a extreme low temperatures, but that probably is only really significant well below zero deg F.
Let's look at fuel economy.
That's somewhat affected by the viscosity. Choose a ligher grade, and you'll get better economy. I believe that the choice of grade has MUCH more to do with economy than does base stock. I agree that base stock does have an effect, but it's truly negligible in most cases; it's there, but barely percieveable.
How about a synopsis of the two UOA examples ...
One guy can basically can run his dino fluid for 10k miles, and get a very nice wear rate and overall performance. The other guy runs his synthetic for 5k miles, and yet gets about the same wear rates and overall performance. Does is seem logical to spend 2x more money ($20/gallon vs. $10/gallon) for the lubricant, and then dump it 2x more often (5k miles vs. 10k miles)? In effect, the "synthetic" is costing 4x more money, FOR THE SAME UOA RESULTS! There is no temperature concern in this environment. There is no real flow or grade issues. There is no significant economy savings.
Bring on the nay-saying, but for goodness sake, bring facts and UOA proof. This is the second post I've put up with some hard UOA facts. If you can't put up good data for your side of the discussion, please leave your rhetoric at home.
To the OP, outsiderwv. Do what you want; you have all the information you need to make an informed decision. If you REALLY want to know, how about trying a few UOAs with two different set up's, then tell us how it worked out for you, rather than ask us what's "best". Run PP with a M1 filter for a few 5k miles OCIs. Then run some PZYB with a common Purolator filter for 5k miles. Do the UOAs and let us know. Pull the valve covers and take some pictures. Show us which one is "better", and if the expense was worth it!