So you don't want to offer a single objective reason why the one I linked is inferior, when I've explained that it works just fine in all respects. I can understand that, it sounds hard to do.
You, and others in this thread made a claim: The Pentax adapter is superior, and you're telling me I have to prove why it isn't? That isn't how these things work. If you make a claim, you back it up, and if instead of backing it up, you say "well prove me wrong" you invalidate any credibility of your original claim. I'm so used to this, when debating theists. "Well prove God doesn't exist!"
Bottom line is, I really don't care anymore. The product I have is fine, and if you or anyone else doesn't want to believe it, by all means shell out to Pentax for something virtually identical. At least the money goes to a company I support. I do think you're spreading misinformation though, unless you can give me an objective reason why the particular ring I linked to is inferior. I don't doubt people have had trouble with some knockoffs, but that's irrelevant to my original query. I'm talking about a specific product that I've had nothing but a good experience with.