I'm looking for the dual wan wifi router. The price is supposed to be ~100$. I'm using Asus RT-AC66U, but I'm somehow unlucky with Asus routers as the first one was just loosing wifi connectivity and this one is getting very hot + loosing connectivity time to time. Wifi signal is supposed to be strong enough (RT-AC66U wifi strength is good).
Any wireless router which has both a 2.4ghz band and a 5ghz band is capable of this, so long as the router firmware permits these to run on two separate SSIDs.
I know your pain with ASUS; I have a similar router from them and I now get drops, strange behavior, and my Steam Link has tons of issues with it, even though it's directly beneath the router and only has one uninsulated ceiling between.
While I haven't replaced mine yet due to expense, I recommend Ubiquiti (my current router) to handle your routing. My ASUS is now just a dumb wireless AP, which helped somewhat but didn't resolve all of the problems. Depending on space, you may want to look into mesh wireless, but as an immediate replacement, I would probably get a Ubiquiti access point to pair with the recommended router.