I have the luxury of the office supplying gear so I went through a few routers to see if it mattered. Yes there are tons of reviews but I'll not link to any and just share.

I changed out the Archer C7 for a C9 and the dual core delivered a lot more (well if you say 10% is a lot) overall throughput.

So my nod is to any decent DUAL CORE fancy AC router. Be sure to update the router firmware and do a factory reset on said router to give it a good clean start. Here I use a Google DNS since it beat out my ISP's DNS (I ran NAMEBENCH to test.)