I used Orbi behind my 5G gateway. Connections wise it was good, but lots of dropped connections, stalled connections, and failure of IoT devices to connect.
(Some of) the Orbis have a 2.5GbE WAN port which means you can get great speeds, but if you want to use parental controls and firewall on the Orbi you’ll be forced into a double-NAT scenario. Putting the gateway in bridge mode seems to cause some reliability issues. (Pretty sure it’s not fully implemented properly on the gateway)
A Ubiquiti Ultimate Dream Machine or a UDM-Pro is a much more affordable alternative with better functionality and expansion options than the Orbi.