I am in the same situation, are you saying its better to use the AX86U as the main router over the AX88U. I thought the AX88U was better?Welcome to the forums @BeerFizz.
The RT-AX68U should give excellent performance as an AiMesh node, in addition to the RT-AX86U, or the GT-AX6000 are the routers I would be considering today. For the latter two, I would make them the main routers and your RT-AX88U the AiMesh node.
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