One more for mikrotik (I run the VM version on a small linux box).
I tested a ton of those (pf/opn-senses, VyOS, even Cisco), and noone of the free ones can handle IPv6 in a reasonable way in 2024, which is slightly bizzare. Mikrotik has some annoyances, but it's rock solid as a router.
I don’t use its container features and instead run podman in a vm next to it. Works great.
OpnSense is incapable of proper DHCPv6-PD, that's when your route receives a prefix from upstream and delegates parts of it downstream. More specifically, it does the delegation, but it doesn’t add the relevant routes, effectively blackholing the allocated prefixes.
VyOS fixed this specific bug since I reported it. RouterOS and IOS never had it.