I don't have one yet, but will soon. Just a few weeks ago, the heater in my
QT broke (cracked) -- don't know how, but it did whether my own fault or not. Imagine my surprize when (without seeing the broken heater), I reach in and ZAP! not a good feeling. Until then, I was of the opinion "why waste the $15 bucks?"
Just consider it insurance. No one PLANS to have a broken heater or fail
PH cord -- if that's all it took, then we wouldn't be having this thread. Fact is, things DO go wrong, whether it's your doing or not.
Matt