I seriously question the additional conversion for runs under 6-8m. A well shielded cat8 ethernet cable is the better solution in that case, even before discussing the quality of PSUs needed for the convertera. The Etherregen in combination with a well clocked switch is a cleaner and better solution.
This didn't hold true in my system using my ears at least...
Replacing ~10 ft of ethernet from a noisy equipment closet to my audio rack with fiber made a BIG difference. I heard a darker background and more clarity/detail, with no added harshness. I terminated the fiber with each of the following: EtherREGEN, OpticalRendu, and $100 StarTech converter (+ after market power supply) and the results were all about the same minus differences between USB and SPDIF (my preference) which I assume to be related to my DAC. All of these were much better than straight Ethernet to the M5 from my perspective.
Yes, my 10 ft run was not cat8 or of high quality, but the difference in sound quality vs copper was so significant I don't think buying a better 10 ft copper cable would have made up all of the differences.
Baseline:
- switch with sfp port -> 10 feet cheap ethernet cable -> EtherREGEN -> short cat8 -> Bricasti M5 -> SPDIF -> DAC
Fiber 1-SPDIF:
- switch -> 10 feet of fiber -> EtherREGEN -> short cat8 -> Bricasti M5 -> SPDIF -> DAC
Fiber 1-USB:
- switch -> 10 feet of fiber -> EtherREGEN -> short cat8 -> Bricasti M5 -> USB -> DAC
Fiber 2-USB:
- switch -> 10 feet of fiber -> OpticalRendu -> USB -> DAC
Fiber 3-SPDIF:
- switch -> 10 feet of fiber -> $100 Fiber Converter -> short cat8 -> Bricasti M5 -> SPDIF -> DAC
I'm currently running the latter as I didn't detect a drop after replacing the more expensive converters. I've been tempted to buy another EtherREGEN to drop back in to see if I would now hear a difference vs the much cheaper converter...