I think the big motivation for the Omnia is the Turris project, not open source per se. Security threat analysis and automatic updates from the nonprofit organization that runs the Czech DNS registrar. LXC, Wireguard, and the customization options from the mini-PCIe slots are a bit of a bonus.

The Omnia doesn’t have great OpenWRT upstream support, and the wireless performance sucks. 2GB of RAM seems enormous for a router, but when I put a medium-size number of clients on it (100-ish), its security monitoring features overran the memory and oom-killed essential services. Fortunately, that can be turned off.

And the Turris project seems to be retreating from modern Internet speeds. The Omnia can’t keep up with 1Gb full-duplex fiber, but they’ve moved onto their next product: The MOX/Shield is even slower. (1.6 GHz CPU vs 1.0 GHz CPU)