I had OpenWRT running on an Archer C7 for a while, but the wifi was "unreliable". It's like the 5Ghz would just randomly stop flowing packets. I never root caused it, but since I stopped using it my home wifi experience has been generally boring in a good way.

I live near main street in a small touristy coastal town, and there's tons of access point beacons flying around. I only have a 10,000 sq. ft. lot and have three access points to cover it. I turned off "legacy" rates everywhere I could so hopefully all my beacons are 6Mbps+ with greenfield preambles.

Different wifi chipsets cope differently with congestion. Specifically, when packet collisions do occur, some chipsets miss both frames, while other chipsets successfully decode the frame of higher signal strength as long as there's enough of a difference. In low congestion areas it doesn't matter since packets rarely collide, but in high congestion areas it can make a big difference for throughput as packet collisions occur frequently.