Not really an intel employee, but I haven't encountered a WiFi router/AP (regardless of enterprise or consumer router setup) that caused speed problems with 7260. 5 Ghz AC is extremely stable on 7260 so any WiFi AC router with stable firmware should work perfectly with 7260 and give you 500 Mbps actual speed out of 866.7 link speed.
I am really sorry for this inconvenience.
Your message was forwarded to the engineering department as valuable feedback.
These are some recommendations you can try in case any one of them was not covered before:
- Install the latest Intel® PROSet Wireless Software 17.1.0. Intel® PROSet/Wireless Software — Intel® PROSet/Wireless Software downloads
- Use WPA2-AES (instead of TKIP) for the wireless encryption.
- Disable uAPSD in the adapter properties. Intel® Wi-Fi Products — TechNote: Access Point interoperability issue with uAPSD
- Use 20 MHz channel width for the 2.4 GHz band. Intel® Wi-Fi Products — What are the advanced Wi-Fi adapter settings?
- Update your router’s firmware.