The Eero Generation 2 WiFi mesh networking devices are great whole home WiFi access points.    They combine the 2.4Ghz and 5Ghz RF bands into a single SSID, they automatically mesh over the best available band or wired network, and just work. At this point I would like to say I am part of the Eero Pro program and sell/install Eero Devices.

Eero now makes 2 types of the devices the Eero and the Eero Beacon.  The Eero is their traditional device with 2 ethernet ports one for uplinking to your internet connection or to mesh with Eeros and the other for you to plug in wired devices.  The Eero Beacon, is smaller,  plugs directly into an outlet, and has no ethernet ports so it is meant as an accessory to the Eero and meshes over the best available wireless connection.

So what does this look like, in our 1 bedroom example:

In the Image we see 5 Access Points shown by the Teardrops with the SSID and band information (5G,2G), and we see 5 of them, which were actually created by 1 Eero and 1 Eero Beacon.  So 2 devices creating 5 ways for us to connect and only a Single SSID, making for a seamless experience connecting to our WiFi network.
What we also see is many red teardrops with a number, this is the signal level we see for our access point, and when designing a WiFi network we want that number to be greater than -70dbm (closer to 0), which every point is.  So what does this mean, in our testing we were able to have a throughput matching our internet connection which for this location is 100Mbps download speed and 10Mbps upload speed.