I can highly recommend looking at the router database of OpenWRT. I had bad experiences with DD-WRT. Mostly stability issues. According to my research, OpenWRT

I can highly recommend looking at the router database of OpenWRT. I had bad experiences with DD-WRT. Mostly stability issues. According to my research, OpenWRT doesn't have as much functionality or router support. But, it's very stable. My favorite feature is both is that you can easily add virtual APs. E.g., I have one virtual AP with net isolation (no access to other networks, Internet only) and clients can't see each other.