If you want to have good speeds on macbooks and best wifi coverage for all other devices, then install hggomes 378.55.4 firmware, Set TX Power to 100% (especially for 5Ghz), enable 802.11d, DTIM Interval = 1, Beacon Interval = 20,
RTS Threshold to 1400-1600, choose channel 36 for 5G, disable WMM No-Acknowledgement in wifi>professional.
Enable all of this: WMM APSD, Optimize ack suppression, Enable WMM APSD, Airtime Fairness, 802.11ac Beamforming, Universal Beamforming, Optimize AMPDU aggregation.
Turn on adaptive qos (do not turn on traditional or fw acceleration will be turned off)
Overclock it. I overclocked my to 1400 mhz cpu, 800 mhz ddr (bogomips 2798)
AC68U