Can you share why you use ZeroTier over Tailscale? I run several headscale control planes and it really is nice to self-host. But, I'm curious about other options.

Not OP but I'm on ZeroTier because it was one of the best free tiers available before Tailscale could run as a Windows service.

Also I believe it implements a lower layer of the network stack so more options are supported, though I haven't needed to investigate in detail.