The best price for the Honeywell RTH7500D 7 Day Conventional Programmable Thermostat is about $70 whereas a cheap Hunter 44550 Auto Save 7 Day Programmable Thermostat costs just $40. One of the reasons I believe for the big price difference is that these two companies are aiming for different sections of the market, but when the two devices are compared they perform nearly identically.
Both the Honeywell RTH7500D and the Hunter 44550 are 7 day programmable thermostats that let you set up 4 heating/cooling periods per day. This is the ideal level of programmability to ensure you never waste any money heating or cooling an empty house. And both these thermostats feature smart recovery which is a function that pre-heats or pre-cools prior to the start of a programmed period. So when you wake up or get back from work the house temperature is just as you want it.
Furthermore, both the Hunter 44550 and Honeywell RTH7500D have the ability to switch automatically between heating and cooling as the seasons change. Also these two programmable thermostats have temporary hold and vacation mode that lets you suspend your settings when you decide to have a day at home or go on holiday.
The main difference between the Hunter 44550 and the Honeywell RTH7500D is to do with compatibility. Honeywell thermostats are excellent for compatibility: the RTH7500D can regulate single and multi stage heating and cooling (2 stage heating and 2 stage cooling). It can also accommodate single and multi stage heat pumps. In comparison the Hunter 44550 can only handle 1 stage heating and cooling and heat pumps without auxiliary heat.
In favor of the Hunter 44550, it has swing control which is absent on the Honeywell RTH7500D. Swing control allows the user to set up a range within which the thermostat ignores small changes in room temperature. This stops the air-con, furnace etc. from constantly turning on and off.
Although Honeywell is the more famous brand for programmable thermostat it might be worth your while (if you have single stage heating and cooling) to buy a cheap Hunter 44550 Auto Save 7 day Programmable Thermostat.