I read it’s something like typical $5 price difference and z-wave have to pass compatibility tests
I initially went with z-wave because
- 900MHz frequency has better range in my house
- compatibility is good
- my local home center had a few z-wave devices but no Zigbee
But I ended up with both, no problem, and will soon add Thread.
I strongly prefer local networks instead of WiFi so I know they’re not calling home, it’s cleaner separation, and allows battery devices
If this were my decision, I’d put batteries as the top decision factor.
If your devices are battery powered, Zigbee/z-wave will last several times WiFi devices before you need to replace the battery. I would get frustrated with this very quickly.
If your devices are plugged in to a reliable source of power, then obviously this is not a factor. Or maybe phrase that the other way: if your devices are WiFi, future you will thank present you if you can find a way to plug them in