@ jbhowlesr
I have benched more cards than I care to remember, Please let me assure you there is a significant difference.
While you are correct with companies such as XFX making cheaper non reference boards to lower their costs, please let me assure you companies like Galaxy, eVGA, Asus, Gigabyte and MSI make multitudes of cards
They are typically marketed toward specific users. High end cards such as the Classified, Matrix, HOF & Lightnings not only are designed to run faster and are able to handle move voltage they are also designed to run cooler with less noise.
They also in every instance use better components, again running with less noise, heat and with longer life spans.
They also typically have a community following that creates custom BIOS files for even better performance with additional voltage and head room.
You may want to do some research on this as it seems you may have been misinformed