Initially, we have Cosmote VDSL 50mbps Down / 5mbps Up, a single-phase old installation from 1992, and a kitchen socket with a 16A fuse (router location) and a socket with a 10A fuse in the PC room. The sockets are relatively close to the panel if we measure distances on the wall and towards the electrical network boxes; regardless of whether it’s a different circuit, it’s the same phase.

It was purchased for a new desktop gaming computer which, unfortunately, is not very far from the router but is located between drywall, a hallway, and a door, with a closet. For convenience, I temporarily used a simple USB WiFi card which worked very well, reaching 44~46 mbps, but for video calls, LIVE, and gaming situations (CS2, Call of Duty DMZ, etc.), the problem with very high ping caused significant delays to the point of frustration...

I am a network and computer technician as well as a programmer.
--- The Powerline literally saved the situation (instant response compared to WiFi, low stable ping in games, a pleasure, everything works instantly, pure speed as if I had run ethernet, it worked immediately without pressing the pairing button, through the 230Vac electrical network reaching up to 300 meters of existing internal electrical wiring where electrical devices operate).
--- It promises over 1000 Mbps maximum speed OverLine and LAN, while more expensive options are limited to 300 and 600 mbps, but I don’t have 1Gbps Internet to test it, unless I connect two computers with fast NVME drives via ethernet cables, one crossover and the other straight, set static IPs, and transfer files to see the max speed.
---- VFM at this price (35€) with the new HomePlug AV2 MiMO standard with rectangular OFDM modulation and AES 128bit network encryption.
--- The limitations and negatives are as follows: it works with a power strip (ONLY if the power strip is simple, not one that protects against surges, and if you place the Powerline in the first socket of the power strip and in the last socket you put a single socket surge protector if you want for surges, and into this you plug another power strip to protect the connected devices (PC, monitor, speakers, printer, phone charger, etc.), that’s how I have it in both parts of the Powerline, in simple power strips in the first socket, and it worked instantly without any disconnection or trace of lag after intense gaming, it gets warm when connected but not burning hot.
---- Now in three-phase installations there will be a problem if each part is connected to a socket with a different phase, you will need to buy a more expensive one, or test in your house which sockets are on the same phase for it to work.
---- Mercusys is a subsidiary of the renowned TP-Link and I believe it will be reliable in the long run since Powerlines, due to their technology, cannot be protected with UPS or surge protector power strips, as these devices block all these frequencies because they consider them interference.
--- It is a very useful network device that should be in every home, especially now in the Fiber era. WiFi from the router to the devices significantly wastes the speed and response of the network and internet you pay for. (Powerline can be negatively affected if inductive loads operate on the electrical network (such as motors, fluorescent lamps, switching power supplies, UPS, microwaves, etc.)
--- I also tried connecting the Powerline receiver to an old Vodafone router as a small switch and extra WiFi Access Point antenna (of course I disabled DHCP so it gets IP from the main active Cosmote router where I have the Powerline transmitter connected, connected the PC to the old Vodafone router and that to the Powerline, and the other Powerline to the main Cosmote router, and guess what, it worked perfectly without problems and with zero lag even in gaming situations.
In the photos below, there is a speedtest measurement as well as the highest recorded by the monitoring program reached during gaming, and that it locked at 1000 Mbps.

Timelessly, it is true that ethernet cable (for me CAT 6A) if you can run it in your space and arrange it without being in the way, ugly, inconvenient, or at risk of being hit, is by far the most stable, reliable, economical, and fastest pure connection, even if you have Fiber, from the router to your PC it covers you, and home networks are still far from speeds above 10Gbps, the copper ethernet cable is king. But if you don’t want to drill holes and run channels, with Powerline you just plug it in and it works. If you have modern devices with new WiFi standards (like mobiles, cameras, tablets, etc. that don’t take Ethernet), a good solution is WiFi Mesh or a good Access Point, because the classic all-in-one provider router will have issues)