I just left a slighty unpleasant review on Amazon about the Inkbird ltc-308.
I have used this twice. Owned it for a month. I'm only using the heating outlet, with a 45-watt heating wrap, for keeping wine/beer warm in primary fermentation in a cold house in winter.
The first time I used it, I had no problems. The Inbird's probe is in a thermowell; I also checked the temperature with a Thermapen. They agreed, usually, with a max 1 degree difference, attributable to the location of the probes.
The second time I used it, I also checked with the Thermopen, and at pitching temp, which in this case was 78 degrees, they agreed. However, days later, (today) I checked the temp of my wine with the Thermopen, and noticed (in horror!) that it reported 90F. The Inkbird was reporting that it was just under 83, and the heat was on. (My setpoint was 83F). The max temp range for this yeast is 86F. But my wine must was 90F!!!
I do not know when the unit failed. But I did notice that the heat was on (red light on) more than I thought it should have been.
I just tested it again, with two other thermometers, including my Thermopen. It seems fine .. (all are reading within a degree or two, which could easily be attributed to location in the warm water I was using to test).
The bottom line is: The Inkbird unit cannot be trusted. Wine and beer making is generally not tolerant to 7 degree "mood swings" in temperature control. I was lucky .. I don't think I lost my 6 gallon batch (transferred today, and the attenuation was as expected), but I won't trust this unit again until I can determine that this error in reading (and therefore trying to cook my wine) was a fluke.
So disappointing .. I'd wanted an Inkbird for some time now. I'll likely use my analog controller as backup next time.
Other than errors, it's a lovely unit .. I really like being able to see a temp reading on the unit. Too bad it's inaccurate!