It's kinda been beat to death everywhere on the Internet. That test is not the ultimate definition of what's good or bad. Besides the difference is not that much anyway. The article doesn't say that HD oil is bad just that is came out worse in the test. Now, I use AMSOIL and have been for many, many miles. It's good stuff. I use it primarily for heat protection. I've also used Mobil 1, it's good stuff. I've also used HD oil for more than a few hundreds of thousands of miles and never had a problem with it. Just use whatever makes you comfortable and kinda ignore manufacturer's claims. If you ignore the bit about the 4 ball test, the article does make a couple of good points about BS that people at the dealers pass on.