No hardline in the house so must go wireless. Bad decision/lack of thought when we built the place 30+ years ago. I have a router upstairs (where the cable modem lives) but needed an extender to reach the basement, which was a PITA. I did not realize until I had it working that it creates a subnet so some stuff is not visible to the rest of the network. Our power is not all that reliable, so had to manually reconnect after a glitch, and some things can not reach the upstairs router (everything there is on a UPS). A power outage meant an hour-plus to get everything up and running again. Much easier now, but I've only had the mesh a few weeks, and this is the first time it messed up. Not sure what glitched, though I've read people have to periodically reboot the routers/nodes.
I am not sure what was up with my AC1900 Linksys router, but it was throttling my Internet speed to about 80 Mb/s, and now with the new ASUS router I am getting 800+ Mb/s. A cable company tech looked at it for a while, and we piddled with settings, but finally gave up and I told him that would be the final shove to update the system.
The good news is I figured out a lot more stuff in the ASUS app, and was able to assign meaningful names for some stuff (still a bunch I don't know), but I am up hours past my bedtime as the system had to work again for my wife to use in the morning.