Our Honeywell thermostats (which appear to be an older variant on
this design) have an "auto" mode where they will do both heating and cooling, based on the schedule you programmed in. Not that I had any idea for the first two years we lived here until somebody told me about it and I had to dig up the user manual online.
So... if all you want is a hard-to-program thermostat that can deal with a/c and heat automatically, you only need to spend $38 on this Honeywell.
(N.B.: if you really and truly want this feature, make sure you root through the whole Honeywell line to make sure the one you get actually does have this feature. The link above may or may not actually have it...)