We recently had to replace our Geothermal unit and it came with the thermostat from the manufacturer. The temperature was up to 4-8 degrees off from the actual temperature of the house using digital thermometers purchased by me. After the installers changed it out with the Honeywell thermostat the temperature displayed was within 1 degree consistently.
For a smart thermostat, it should be able to switch heating and cooling modes automatically. The only smart thing about it is that it connects to the internet. I have a non-internet-connected thermostat in my other home that can automatically switch between heat and cool cycles.