Since you posted this thread twice I will post my response twice, haha.

I'm going to go against the grain here.

I use Ranco or Johnsons for the most part, I don't find the herpstats or helix thermostats worth the money. I have been using a number of different thermostats through out the almost 7 years of keeping snakes to find what works for me. I also use the A-life and Zoo-Med repti-temp thermostats. I bought the zoo-med as my first one 7 years ago. Today I use it to control my ambient temps on one of my racks. I have had zero issues with temperature control.

With all of the thermostats mentioned above I think it is more important to have a quality temp gun that you can check your hot and cool spots every other day if not daily. Every thermostat can malfunction no matter how much money you spend on it.