I was getting sick of the Billion 7800 anyway and having to constantly restart it all the time. It's a good router if you don't want to go higher up the food chain and look at some of the Asus Nighthawk stuff that is double the price with a broadcom chipset. Being on 4.5km of line underneath me I didn't really have that much of a choice.
It's been running faultlessly since I installed it, and it syncs at a faster speed than the 7800 ever did. That said I'm not doing anything spectacular with it yet, half of my existing home network got fried last week, so I'm waiting for the Apple TV 4 to arrive so I can start looking at homekit, as well as a new USB printer and a few other things to add.
It's easy enough to use and has a wizard interface that does everything you need. The Archer D9 is out by now but the D7 ticks all the boxes, especially if you're on a long line, and you can bridge it with an Airport Extreme should you prefer the Apple ecosystem.