I just got FiOS last week and missed the rock-solid nature of my R7000P so after trying to make it work with Verizon's G3100 router, this morning I swapped it out for the Nighthawk with DD-WRT (6-18-19 Kong). Not worried about any restrictions by using my own router as none of them apply to my setup (I run a TiVo on a cable card so no need for the G3100 in this setup).
The issue now is that I went form ~950 up/down to ~200 up/down and I'm clueless as to where to start looking.
Is anyone else running this setup and have any ideas what the bottleneck might be?
Go to Wireless-- Basic Setting-- TurboQAM (QAM256) support "disable it" reboot your router. test your speed... let me know if this fixed your issue...