I'm starting out on home automation with a Raspberry Pi (2) and planning to purchase a Z-Stick Gen 5 z-wave controller and run OpenHAB.

For heating controls I've read mixed views on using a smart thermostat (e.g. Nest) and controlling via a HA application as the smart thermostat is trying to learn and the HA is controlling via settings (e.g. temp, nobody home, etc.).

What would be the best type of heating controller (z-wave or WiFi) to buy please?

Heating system is a combi boiler and I would need the residents to be able to set/override temp settings etc. via the thermostat or through an app.