Completely depends on what features you need. If what you need is being met by the Tstats then you’re good. SmartThings integration has it’s own quirks and you should always look at the weakest link in the chain for any setup.
For your unoccupied or semi occupied rooms/floors I would recommend using the motion sensor based thermostat, you can define a timeout after motion is detected and use remote sensors. This should be the most efficient way to infrequently used thermostats.
You can also combine it with a regular 5-2 thermostat with a schedule or mode
The beauty of ST is the ability to combine smart apps to create custom scenarios. For e.g. you can use both the Motion and 5-2 day thermostat smart apps together like this:
- When in mode home, use the 5-2 day thermostat (this is when you’re around the house/rooms and want it always temperature controlled) and have the motion based thermostat inactive
- When in mode night (or any other mode, say weekend) the motion based thermostat is active and 5-2 day inactive, this way it only turns on when someone walk into the room