You can't judge final shipping frequency or performance of a silicon device based on what a pre-release beta part does. About the only thing that you can judge is that the performance or final frequency is not likely to be less than the pre-release part. But even that is uncertain. Pre-silicon samples are used to evaluate a wide variety of things like power delivery systems, thermal dissipation, compatibility, etc. They are not intended to be the final product.
I seem to remember writing practically the same thing when the discussion was regarding the clock frequency of early Hammer samples, so it's not like my reply varies by the product or even the company that I'm talking about. Don't guess at the final product based on anything that a sample does.