Haven't looked at it yet. My experience with Pennzoil was way back in the 90s. I'd been using it cause that was what Jiffy Lube had. Then someone told me they had Havoline and tried that. Never went back. Also some guy said it was the Pennsylvania oils that had wax in them. I though he was referring to Pennzoil and Quaker State. Don't really know. Could all be bias.
I worked for two MasterCraft ski boat companies and they adopted PennzOil oil & filters after '98- the service trainer said it was just a corporate cooperation agreement and if he had wanted to tell us that it was bad, he would, being a Professional Engineer. I think his licence could have been at risk if he didn't comment on something that might cause problems and considering the fact that he was responsible for the service training program, some of the design, most of the initial testing & validation and had the ability to test frictional losses in engines on one of his dynomometers, it would have been easy enough for him to test. He's also one of the most honest people I have ever met.
I met several people from the GM Desert Proving Ground through my friend who had also worked there- their consensus was: Keep it clean, don't overheat the engine and the brand/type is of less importance. However, after all of the tests they were involved with, most preferred Mobil 1. I had a '90 Silverado that used Mobil 1 until about a year after I bought it with ~200K on it, then switched to mostly Valvoline high mileage/semi-synthetic. I sold it with over 350K and it didn't smoke or use oil, the Astro I drive now has 280K and it doesn't smoke at all, even at first startup. One thing I do, though- I use the larger version of whatever filter is standard- the Silverado got the PF-1218 rather than the PF-25 equivalent and the van gets the AC PF-52 or equivalent, rather than the little stumpy one it came with.
