When I swapped out my EtherRegen for the Network Acoustics Muon ethernet filter, I heard a nice improvement. I did this because I was focused on adding linear power supplies to every network component, and adding one to the ER cost about the same as the Muon, which is passive. My chain is Arris SB8200 cable modem, Ubiquity EdgeRouter X SFP (wifi access point for the house is isolated from the router by optical - another nice bump here), Cisco 2960 old school switch, Buffalo BS-GS 2016 switch, Muon ethernet filter (without the NA streaming cable), Allo DigiOne Signature streamer, Schiit Bifrost 2/64 DAC. Supra CAT 8 ethernet cable throughout, Apogee Wyde Eye BNC cable from streamer to DAC.
Everything matters
I have now been tinkering for 10 years with my streaming set up and the principal lesson learned is that everything matters. Think about it: from the wall outlet to the router to one or more switches to the streamer and dac, the latter three dependendent on clocking and all of them depending on cables and power supplies), it stands to reason that e.g. changing a USB cable is very likely to compensate for a weakness in the chain, that if addressed, would result in an overcompensation by that cable. Therefore I look at individual component or cable reciews with a very jaundiced eye. It is the performance in the context of the individual chain, that matters. As a result I have had numerous ethernet or USB tweaks, be the filters, isolators or processors, cables and LPSs in and out of my chain. For what it‘s worth, the biggest impacts ranked on SQ I experienced were from inserting 1. Etherregen, 2. LHY Audio UIP, 3. 10m clocking of Dac, UIP and Etherregen and 4. LPSs on router, switch and Etherregen.
My main point though remains that praising individual components irrespective of the digital chain is borderline meaningless