When my thermostat died on me (ok, it didn't actually die, but it lost Z-Wave connectivity which meant I'd have to manually raise/lower the temperature instead of it being automated like it used to be), I started looking for a replacement. The thought of replacing it with the same model seemed easiest. I knew how to use it. My home automation system was already configured to work with the model. Plus, I wouldn't have to worry about whether or not the new thermostat would fill the (unpainted) space on the wall, which could mean a much bigger job, or a wall that doesn't look all that nice.
I've had a Honeywell Z-Wave Enabled Programmable Thermostat for about 2 years now. I originally purchased it because being a Z-Wave thermostat, it went well with my Homeseer automation system. I'm also quite a techie geek, so the large touch screen weighed in pretty high on my decision as well. Within the last 2 years, the thermostat lost Z-Wave communication a few times, but not enough to drive me crazy...until a few weeks ago. It started losing Z-Wave communication every day.