Fios Gigabit w/AirPort Extremes

Sorry, confused.

You first post indicates that.......We've always used a trio of Airport Extreme's to "Create a wireless network" placing one on each floor of the house and it seemed to work well.

The "Create a wireless network" setting is used only if an AirPort connects to the network using a wired Ethernet cable connection.

Your follow up indicates that....... I should clarify that only one Extreme is connected to the router via Ethernet, the other two are simply connected wirelessly. The one that’s connected via Ethernet is set to create a network while the other two are currently set to extend the network.

This would be the correct setup if your "main" AirPort connects to the Fios router using a wired Ethernet cable connection and the other AirPorts connect to the "main" AirPort using a wireless connection.

You may have to change the name of the wireless network and password on the main AirPort if your new Fios router is using a different name for the WiFi network and password than your "old" FIos router. And.....you'll have to set up the two AirPorts that are extending the network again as well to extend the "new" named network.

Here, I am assuming that you want the main AirPort to produce the same WiFi network that the new Fios router is using.......so that you will be using all of the AirPorts for extended WiFi coverage.

On a separate note, ideally you would want to connect all the AirPorts using Ethernet if possible, since the "Extend" setting using wireless will always result in a loss of half or more of the potential WiFi speed on the network. There is no loss when the AirPorts, or other routers connect using Ethernet.

In terms of best performance.......the rankings from best on down would go......

Router connects using Ethernet

Mesh system......(not offered under an Apple brand)

Apple "extend" system consisting of one wired AirPort and others connecting wirelessly

If you want to continue to use the AirPorts to provide additional WiFi coverage for the Fios network, you will have to start all over again to reset and then reconfigure the "main" AirPort that connects to the Fios router using Ethernet to Create a wireless network that uses the exact same wireless network name and password that the Fios router is using.

Then, both of the other AirPort Extremes that connect using wireless will need to be reset and reconfigured again to extend the WiFi network that the "main" AirPort is now using.

The big question here.......because the AirPorts are not an exact match to the Fios router........will be whether WiFi devices will automatically "switch" from the Fios basement signal to other signals that are being provided by the AirPorts when you move the devices to other locations around the house. They may or may not do this. Or, some devices may and others won't. No way to know until you try.

If things work OK, then it might make sense to hold onto the AirPorts and use them for another year or two. If things don't work, then you will need to replace the AirPorts with products that will be exactly matched to the Fios router. You will have to ask Fios what the best solution would be in that case.

In order to get the best speeds and WiFi coverage from our new plan should we replace the Extremes with something else? The G3100 has WiFi 6 certification.

The most recent version of the AirPort Extreme was designed in 2012, so it represents technology that was available at that time about 8 years ago. "Long in the tooth" 'might be a polite way to describe the AirPorts these days.

That being said, there is nothing wrong with using the AirPorts.....if......they will provide the performance that you need. Security wise......if that is important to you.......the AirPorts are frankly out of date.

Bottom line......you won't really know how well.....or if....... the AirPorts will do the job that you want unless you try them out in your home. If you can get another year or two out of the AirPorts, that will give bleeding edge stuff like WiFi 6 some time to stabilize.

If the Extremes are still adequate should we change them to "Extend a wireless network" instead?

No, the "Extend a wireless network" setting is used only when an AirPort router connects to another AirPort router using a wireless connection. This setting would be incompatible with a 3rd party WiFi router.

Your post indicates that all of your AirPorts are connecting to the network using Ethernet, so "Create a wireless network" would always be the correct setting to use with this type of connection, no matter whether your main router is a 3rd party product or another Apple router.