I help manage a website based on Magento and whenever I want to hear the sound of crickets, I post a technical question to its user forum. If it hasn't already been asked and answered, you're pretty much screwed.
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I experimented with HPNA in the 2.0 era (around 2001) and found that it over delivered as far as throughput. Its throughput buried the equivalent Wifi and it was rock solid even during simultaneous use of the copper with analog phone calls and DSL connections. But then the HPNA manufacturers abandoned the market. I don't have faith that anyone credible will come in to implement the HPNA 3.0 spec.
I've since given up on the mis-application of copper media and have instead gotten out my drill, drop chain, and fish tape and recommend you do the same. Gbit over CAT5E is cheap and reliable and will be around for many years whereas the non-standard interfaces will fall by the wayside.