I am a big supporter of the GCS thermostats. I have all of my adult breeders moved over to their thermostats and love them. I have had one problem and it was fixed as quick as possible (required shipping me a new control box which was there in two days). The unit I have has built-in night drop which works like a champ and it also includes an audible alarm (with adjustable paramaters...mine is set to '5 degrees off temp for 15 degrees' produces an alarm) and it's enough to wake me up from upstairs.
I had always used Helix units in the past but when comparing what I was going to have to spend for (4) Helix DBS-1000 units with night drop cords, I was looking at $140*4 for a total of $560. This one cost me $269 shipped, it takes up less room, allows for more wattage, includes the alarm, and requires only one wall power outlet. I'm very happy with it.
Hit me up personally if you have any other questions. If you're in the Indiana area and would like to see mine in action, just let me know.
Happy herping,
Jason @ Jason's Jungle