The D-Link Powerline Av-2 1000 works pretty well. Installation was easy; there was nothing to fiddle with. You plug one of your adapters into the wall and an Ethernet port on your router. You plug the other one into an outlet near your computer and connect it to the computer with an Ethernet cable. The kit provides two Ethernet cables, though they're pretty short (3'). Speed was pretty good. I tested with Ubuntu on Firefox, and here are some comparative results:
- Powerline on Ubuntu - max 8.3 MB/sec; sustained ~7 MB/sec
- Same as above, but plugging Powerline into a power bar - max 3.5 MB/sec; sustained < 3 MB/sec
- LinkSys USB wifi dongle on Ubuntu - max 17.8 MB/sec; sustained ~8 MB/sec
- Direct Ethernet connection with Firefox on 2014 iMac running MacOS Big Sur - max 31.5 MB/sec; sustained ~25 MB/sec
It surprised me a bit that the USB wifi dongle was faster, though not much on a sustained basis. I'm guessing that the degradation through the house wiring is greater than that in the air. My computer is about 7 m away from the router, both on the same floor, with 1 wall and part of another separating the two and the kitchen in-between. Download speed took a big hit when I plugged the powerline adapter into a power bar at the computer side. This cut the download speed in half relative to plugging the powerline adapter directly into an outlet, but even there, the speed was 4-5x greater than when I tried the same kind of setup with a range extender and an Ethernet cable from the extender to my computer. (Also plugged into the power bar; I didn't know at the time that power bars degrade the signal.)
So is this worth buying? Assuming that your house wiring is OK and you can plug both adapters into plugs using the same panel box, and your wifi connection isn't so good, then I would say yes. I suspect that the degradation rate with distance to router and walls between them is greater with wifi than with this device. In my case, I think that it was the opposite only because I have a relatively ideal wifi situation. So why is this worth it to me when the wifi connection is stronger? It's specific to my 2019 iMac. My internal wifi doesn't work on Linux and for some reason, plugging in any more than 3 usb devices into this device causes it to freeze most of the time when booting up Ubuntu 20.04 LTS. (For some reason, 20.10 is fine, but it has a brightness problem that 20.04 doesn't have.) My usb wifi requires a 4th usb port. The other reason is that my Linksys usb wifi needed a non-automatic driver installed, so when testing a different distro, it doesn't see the wifi whereas it always sees an Ethernet connection. If the powerline keeps running like it is now, I would say it's worth the extra $80 to me.