I use a Nordost QB4 with both QV2 and QK1 plugged into the two outside receptacles. I use the QB4 only for whichever power amp I’m using, only one plugged in at a time. When I first picked up the QB4 I did not use the ground post at first but later made up my own cable using what an Electrician would use, No. 10 insulated ground cable I picked up at the HomeDepot. On the QB4 side I picked up an AudioQuest gold plated speaker spade and on the other end of the ground wire connects outside to an 8’ buried ground rod. I’m not saying the difference is drastic but it is there being with using the ground the noise floor is lower and especially on my Pass amp it really opens up and with a sense of you’re more there and not listening to a HiFi. I needed a 20’ of cable which one from Nordost would be probably more than I’d want to spend. Very happy with the cable I built for less than $50, plus the grounding rod and clamp.
All my other components go through a PS Audio P10 on its own dedicated circuit. The Nordost is on its own circuit which I only use for my power amp, either a Pass or a Cary.