When companies test their products, they are NOT going to release negative results about their own products. It’s no secret that I’m a believer in the Amsoil product line and have experienced their performance advantages since 1976, when I first started using Amsoil in my own engines. So, with that disclaimer out of the way I’ll say that my inquiring mind always looks at how the competition compares.
I came across an interesting YouTube that did a basic comparison of Amsoil and Royal Purple. Having heard all the ‘sales’ pitches about Royal Purple at car shows, I’ve always thought of it as a good product. I’ve never had a reason to want to change from using Amsoil, but wondered how Royal Purple could be a lower cost if it was as good as Amsoil. So, this video was a great comparison without getting too technical.
Hopefully, this link will stay up and allow you to see the comparisons: Is Royal Purple better than Amsoil? Let's find out! - YouTube
I like the fact that this comparison is done with both new (out of the bottle) and heated (simulated used) oil flow tests. Both new and used oil needs to deliver protection to internal surfaces at start up as well as full operating temperatures. The lubricity test is also important for internal wearing. All metal-to-metal surfaces inside an engine are going to have wear throughout the life of the engine. High lubricity will protect the engine, reduce breakdowns and extend engine life.