I’m not sure about compatibility and I’m too tired today to look it up so hopefully other people will respond.
As far as choosing between identical models except for protocol, Z wave is typically a better protocol for fixed position devices like locks and motorized window shades because Wi-Fi, particularly boosted WiFi, can interfere with zigbee communications, and there’s no interference with Z wave. Since sometimes the solution to this kind of interference is just to move the device a foot or so one way or the other and that is not an option with a doorlock, zwave tends to just be a little easier.
But both protocols are good, and there are people who have only zigbee devices or have only Z wave devices or have some of each and all the set ups work fine. It just depends on the individual details of how each household has laid out their devices and the local architecture.
But in general for locks I would probably go for Z wave because of the Wi-Fi issue. 
http://thingsthataresmart.wiki/index.php?title=Z-wave_versus_Zigbee