Admittedly I haven't tried the newest models, but my experience with Linksys hardware and either ddwrt or tomato was pretty bad. Run for a couple of days and then require a power cycle. Seemed like a hardware issue.
WRT1900ACS is pretty good with DD-WRT (uptime can be until next firmware update). Linksys also sell special set of antennas, which improve signal range (costly but can be worth it depending on your situation). I think they target it for network enthusiasts, rather than very wide market, so they put some effort into quality there.
Counterpoint: I run dd-wrt on a TPLINK el cheapo something at the office, to connect all the boxen and let me SSH into each of them (port forwarding 19 to 22 on box1, 20 to 22 on box2 etc). It Just Works, never had to reboot it in four years now. (WiFi is off though.)
dd-wrt has gotten pretty bad. They don't publish new releases anymore you just pick a daily build from one of the random people who publish builds and hope it doesn't brick your router. Learned this after bricking my router :(
I think their main developer (Brainslayer) publishes his builds periodically. So those aren't random people. But in general it's not really a fully open development project. I.e. it's not governed by any community.
OpenWRT is better in this sense, but even there some people split into recent LEDE project: https://www.lede-project.org
Regarding bricking. Linksys WRT1900ACS is designed with that in mind. It has two partitions, and you always flash updates to another one, so if something goes wrong, you can easily switch to the other partition which will hold previous installation, using special on / off sequence. It's a neat idea, and more routers should follow it.
