Before that I briefly had a Netgear Nighthawk R7000P and it kept interrupting long-running TCP connections. After much back-and-forth with their useless warranty department, I just returned it to the retailer.
They're both cheap and quite good. They're what GL.inet used to be when i last purchased routers before this.
See also: pfSense, OpenWrt
I like the small Qotom Q305p 3205u computers for this, but any small device will do and if you don't care about the router being small and quiet, any form factor PC will work... just need two or more NICs to route packets from one network to the other.