The Mobil 1 0W-40 was developed in partnership with the SRT engineers back in 2004-2005 if I remember correctly, specifically for the 6.1 SRT motor. They have changed the formula a lot over the years as environmental standards have changed. Like has been mentioned above, there seems to be a lot of ways to formulate it to get to get the same basic properties...but it's definitely not the same as it was. That said, I have always run it and done my own oil changes until I got this Redeye which came with 5 or 6 oil changes from the dealer under the extended warranty plan - I've already used 4 of them in a year and a half lol.
The one thing about the new Pennzoil, I mean you have to love that Ferrari runs it, but it's made from natural gas, which is supposed to be very different from other oils. I don't know much about specifics when it comes to that - anyone??? "They" claim it matters and is an advantage.