old thread, i know but fwiw, my rog gt-6000 has now been relegated to mesh service. the ax88u pro is more powerful and with vlan more useful. in fairness, at one time, they were both running with merlin-ware (3004). where the gt6 was king. on a goof, i decided to swap roles; couldn't turn-around for the difference though (a southern adage).
recently, swapped them back after upgrading to 3006 (stock). rinse and repeat with the ax88u pro. the pro was demonstrably better as the main, especially with reach. as a result, the 5ghz connected gt6 now provides superb mesh service to clients on the first floor - a thing of beauty. when merlin's 3006 releases, i'll retest. not a fan of the clunky fusion ui although it has improved.
...