I hate the stock analog thermostat. You cant fine tune it. I spent 3hrs making minute changes until I got it to the comfortable temp. That lasted three days. Then she MOVED it.
I was very sad and wont mention that she locked me out for three hours until I promised to be reasonable.
Nothing but tropical storm rains here for two days so I went to Home Depot and bought Honeywell RTH2300B digital with backlit light. I got it installed. Very easy. Red=hot, White=furnace. Green=fan Yellow=AC compressor No connections to the other wires. Works like a champ holds temp to +-1 deg. Life is good