Product review (5 stars): Very good for the money.
I bought 3 of them because of the price being very attractive and free shipping. It took a while to get them since it seems they get shipped from China. But this was expected and therefore I did not mind.

Besides the temperature and humidity, the monitor can display the time or date (and also have an alarm which I have not tested it yet). By default the temperature is in degree C, but I was able to easily change it to degree F (they have a switch on the back side, but I needed to use a pin).

The 3 monitors converged to almost the same temperature and and humidity after a while. Of course, there might be some slight fluctuations. All of them compared decently well to the AcurRite (613) temperature and humidity monitor we already had and also seem in good agreement with the thermostat setting.

I would like to say that the AcuRite monitor (which costed significantly more) does not show the time or date. Although not that important,  this one shows the temperature with one digit accuracy (AcuRite shows the temperature without any digit). So basically, one get more functionality for about half the money.

I cannot say anything about the reliability since I just got them. I hope they last (at least for a while).