Just as an example.

I have one of the older model Herpstat II's, and it came with the original white, flimsy probes instead of the heavy-duty grey probes. One night, one of the probes failed(at 2am no less), either by being bent or it just failed.. Either way, that thermostat shut that section off and made this high pitched wailing alarm. It was quite obvious that it didn't need help shutting itself off or regulating itself. After about a month, the other probe failed too, but the unit shut that section of the thermostat off, and beeped at me. At least now those t-stats come with the heavy-duty probes and it's unlikely that the probes will fail again. If they do, I trust the unit to take care of itself.

If I did want to back it up, all I would have to do is get a Johnson Controls or Ranco, plug it in to the wall, set it about 5 degrees higher than what you want your hotspot at. Then plug your Helix or Herpstat into the JC or Ranco, set it to what you want your hotspot to be, and that's it.