I decided to do a simple test this evening to see how accurate my thermometer and thermostat is. I taped both probes inside one tub, side by side, right on top of the flexwatt.

My acurite is reading 89.4, and the thermostat is reading around 93. There's about a 4 degree difference, even tho they're basically in the exact same location...

I dunno which one to believe is the more accurate one