I took the recommendation from someone here a couple years ago on the eero and it has been fantastic. I am on a 3 level home with one eero on each floor and we have full coverage at full speed everywhere. I am on Verizon Fios 2gb.
You really should start by figuring out exactly what coverage your single router is giving you. If your impression that “it’s good everywhere” is accurate, then additional AP(s) might not buy you much. Find an app that will let you read out received signal strength (RSSI) in dBm, and walk around the house, poking into corners and such, to see what it is everywhere. If it’s no worse than -65dBm anywhere, and significantly better than that (say, -55 or better) at the spots where you want top wifi performance, then a mesh setup likely won’t get you much. As for what to use to test — mine is an Apple household, so I can only tell you that a Mac will tell you RSSI if you just option-click the menu-bar wifi icon, while on an iPhone you need a scanner app, but Apple’s free Airport Utility will do as a bare-bones scanner. (You must enable its scanner functionality in Settings after installing it.) Maybe somebody here has recommendations for Windows and/or Android scanning.
The fly in the ointment is that if you want single-device wifi performance better than 500Mbps you are going to need to go into the 6GHz band (wifi 6E or wifi 7), and that does not penetrate walls/floors as well as 5GHz, so even if coverage looks fine in 5GHz it might be less great for 6GHz. Do you have or are you thinking of getting 6GHz-capable client devices? Or are you just looking at that fiber connection as “a pipe fat enough for several people to share”? (Some clarity of thought about what you hope to get out of this would be a good thing anyway.)
The 6GHz thing is a tough one for me because I think the only devices I have that can use it are my (and my wife’s) phone. So everything else would be on 2.4 and 5. But I don’t hate the idea of future-proofing.
I had my eyes on the TP-Link BE550 and it has the EasyMesh infrastructure so I could always turn it into a mesh system in the future if I want better coverage.
I had the Eero for several generations and was happy with the mesh network. A regular router just wasn’t cutting it in my 2100 sq ft split level; I’m assuming because of where the fiber came into the house, the router wasn’t positioned well.
The Eero’s frustrated me about a year or so ago; something about them refused to play nicely with the HomePods, which would randomly refuse to connect to the network and require a full reset either by plugging into my MacBook or, for the full size HomePods, standing on one leg whilst holding a hanger in one hand and tapping out a random Morse code on top of it with the other.
I wanted to stay with a mesh system and read good things about the Linksys Velop, especially their app. I remember having a Linksys a million years ago and it being trouble free; the Velops were not. Devices wouldn’t connect, mesh slaves would randomly drop off line, etc. Thank heavens for Bezos and his lenient return policies.
I next tried the Orbis, which worked well and had fantastic speed and coverage. Alas, she who must be obeyed hated how they looked.
I swapped out for the Asus ET12s, which are 1000% overkill but have been nothing but reliable. Surprisingly my wife hasn’t hated the looks, which are a fully industrial gameresque wet dream. The app is solid and offers way more functionality than I need or want; they have a built in vpn for when you’re out and about; and, they play nicely with my Apple ecosystem.
TL, dr, I’ve been a big fan of mesh for the ten years or so we’ve been in this house.