The nice thing about the Ubiquiti routers is that you can have them wired to create an extended network, rather than creating a mesh or wirelessly extending. The downside to extenders and mesh stuff is that you lose bandwidth to the "extending" APs needing to talk to each other and/or the "main" AP. If you have the Unifi APs attached to ethernet, they'll coordinate handoff over ethernet and you'll get the full bandwidth between each AP and the clients attached to it.
(Additional apologies for extending the off-topic discussion, but I *really* like my Unifi APs.
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