I also had the Cisco Valet series. (The M20 I did find Tomato for that). I really liked how they had the USB setup dongle....even my 80yr folks was able to setup a Valet series router just fine.
The last newer Linksys I have used is the EA2700 smart router. I did like the look of the firmware and the nice smart phone app. But it took a while to boot and the range was not quite as good compared to the e2000 with tomato on it. Also, the EA2700 is not 3rd party firmware compatible. I sold that model on craigs.
I also have used a few Belkin routers, and I have nothing but bad things to say about them(except for the tiny Belkin travel router I have). And most of the major retail sites have mostly bad reviews on Belkin routers. I wasn't happy to hear that Belkin took over Cisco/Linksys consumer networking products. Most of what I have read in reviews etc about Linksys routers since then were not that positive.
I have had too many Netgear products fail on me so I will never use them again. I ran my trusty Cisco e series routers for a while, until I wanted to upgrade. Asus started making routers and what good reviews they have. Got my N56U and was/is awesome(padavan firmware makes it much better).
Then upgraded my laptops card to an Intel AC7260 and got a Asus AC56U. Was a bit bumpy start until they worked out some bugs in firmware, but now its the best router I have ever used. I LOVE the look of their firmware.
I have no intentions to purchase another router anytime soon. Why? Because my laptop is maxed out already. It is only a 2 antenna laptop and thus can not make use of the higher bit-rate AC wifi. (866mbps is what the Intel AC7260 and Asus AC56U supports on the 5g band) I have tried adding an antenna, but that seems to have made things slower and more unstable in my tests. Also, my wired systems all perform fine. (Even my the Cisco E series handled wired routing fine). Also, I do make use of the OpenVPN feature in my AC56U. (I am not sure if this new Linksys WRT1900AC has built in OpenVPN support like the Asus routers do.)
I am very curious about Belkin/Linksys "re-launch" of the WRT series.
(I loved the old "blue boxes" that were the Linksys WRT series. I see those things at thrift stores all the time now. Those old B/G routers always had excellent range and still every one I have fired up just for kicks works perfectly.)
I love tinkering with the newest stuff and certainly want to see what the community will think of these new batch of WRT's and see if they are deserving of the historic model title. Plus, it is always good to be ready for the future.
For those who don't know much about the old WRT series...watch this vid I found:
https://www.youtube.com/watch?v=dwCenZMp-gY
Update: New beta firmware available for the AC68U that is reported to fix the recent issues. (and btw, the issues was caused by Broadcom's sdk, not Asus).