I’m using Pihole in LXC container with Debian. So it’s running on Omnia (hardware) but virtualy. About Knot … I’m not sure. After you install it you must uncheck the option “Use DNS servers advertised by peer” (in network-interfaces-wan-second window) and to the new line you must write the IP of Pihole. The advantage of Pihole is functionality - adblocking, you can do parental control (DNS blocking), now speedtest and probably more and it runs as a virtual machine so you can always turn it off without losing the real hardware.
The ad blocking is as good as your block list - so you must add some lists from forums for good functionality. In my case it isn’t 100/% working (but I’m lazy and using adblock in internet browser too, so when Pihole can’t block it adblock on browser has it and sometimes its reversed - adblock in browser can’t block it but Pihole can). There’s YouTube blocking lists on forumsso yes it blocks YouTube ads. I like the whole functionality of Pihole - not just adblocking and the good thing is that it works (with LXC) on Omnia in one device so there’s no need to connect another device.