Hey guys!
I second Scuzzy. I actually had the RT-N66U for a few years, but it started randomly rebooting once a day. I too picked up the ASUS RT-AC68U, and it is a fantastic improvement. Primarily, the wireless range and speeds. I get 400mbps on my Google Pixel 3, even one room over. It seems to handle heavy traffic far better than the old N66 as well, probably due to faster processing.
Anyways, it's a great router, but don't pay more than $150 for it, I see some crazy prices on them...
Current Primary PC:
AMD 5800X | MSI X570 Carbon | G.Skill 32GB DDR4-3600 16-19-19-39 | MSI GamerZ RTX 3070 | ADATA 8200 Pro 1TB NVME | Micron 1100 2TB SSD | Crucial MX500 2TB | Seasonic Gold 750 Watt | Fractal Define S Case w/Tempered Glass | Noctua NH-D15 CPU Cooler | Sound Blaster Z | Noctua 4x 140mm, 1x 120mm Chromax | Pixio PX7 & PX275H Monitors