I currently have an RT-AC68U as my main router in my basement (25% of my clients are located trhere and they run fast on 5G). I also have (75% of my clients upstairs) on the first floor and they run much slower. When I run a speed test downstairs near the single AC68U router (5G band) I get 220 down and 10 up. When I run the speed test upstairs on the same client I get 54 down and 6 up due to distance increase from the router downstairs. My goal is to maximize WI-FI performance which results in the fastest speeds on both floors. Therefore I am planning to purchase another router either a (AC86U or another AC68U) to setup an AIMesh system. If I purchase an AC86U it will be used as my main router in the basement and the existing AC68U will be used as the node upstairs connected via ethernet backhaul to the router. Question #1: Which setup would result in the fastest performance on both floors (AC86U router and AC68U node) or( AC68U router and AC68U node)? Question #2: Can I expect the Wi-Fi performance upstairs with clients connected to the AC68U node to be just as fast as clients currently connected in the basemen to the AC68U as the main router? In summary I don't want to spend approximately $100 more for the AC86U if another AC68U in an AIMesh will perform about the same speed in my config. I really appreciate any advice you can give!!!