Customers most agreed on the following attributes:
Comments about Honeywell Honeywell Prestige IAQ Deluxe Comfort System - YTHX9421R5010:
[...] unit installed easily and is functioning perfectly. The outside and remote thermostats are excellent features that connected flawlessly as well. I recommend this for anyone who wants to have a programmable thermostat as well as controlling a whole house humidifier.
Comments about Honeywell Honeywell Prestige IAQ Deluxe Comfort System - YTHX9421R5010:
This is the best thermostat I've ever used. Although I'm an electrical engineer, on all prior devices I've had to consult the (often poorly-written) manual to understand multiple menu layers when changing heating schedule, etc.
The Honeywell Prestige thermostat is self-instructing for all functions.
Traditional thermostats sense only at the main terminal, customarily located in a central area. The Prestige's remote allows one to regulate the temperature elsewhere -- in our case, in a small bedroom -- with consequent heating-cost savings.
We use the thermostat to control a Lennox SLP-series variable/condensing furnace.
I am so impressed with the Prestige device that I purchased a second one to replace an older Honeywell digital thermostat in another house !