Product review (4 stars): Not 100% accurate, but good for money
Purchased this primarily for the humidity function and the small-ish remote sensor that I can put inside a cigar humidor to validate the existing gauge humidity sensor that is in it.  I first wanted to gauge the accuracy of the sensors so I did a salt test by putting both sensors inside a sealed plastic canister with a small cap of wetted salt.  I found that the two humidity sensors were very close to each other (external read 72% while internal read 71%) but should have been approx 75%, so there's about a 5% drift, and there's no way to calibrate the sensor.  I can deal with this.

Temperature sensors seem very closely aligned, reading the same temperature, however I have no way to verify accuracy against another sensor.

Overall, I think a reasonable purchase.