The problem with the Unifi accesspoints (I used an AC Pro) is that their reach is quite a bit lower than standard cheap access points such as a TP-Link Archer C7. The only way I'd get decent coverage in my house was to install a bunch of them, but then you'd still not have seemless handover.
At first I reverted back to My old solution of the TP-Link AP and a Netgear repeater, but once the second gen Eero came on the market, the choice was easy.