Purchase on 10/10/2025 for €49.9 and after 1 month of use.
Positives:
Indoor unit: Elegant and small, which is also easy to read and can stand upright. The ability to adjust its brightness is also good.
Outdoor unit: Also small, with good range and connection.
Negatives:
Indoor unit: It resets every time there is a power outage and you have to re-enter (manually) the date, time, etc. (it does not take batteries).
Outdoor unit: The package included one (1) outdoor unit. The deviation between the indoor and outdoor units (see image) under the same conditions is 0.3°C and 2% in humidity. Compared to another digital thermometer, there is a difference of 0.8°C. There is also a significant delay in its adjustment to rapid temperature changes. It took 20 minutes to correctly display the room temperature.
I had for 10 years a very fast TFA worth €70 (which was also a digital photo frame) and it automatically synchronized to the correct time-date settings every 12 hours.
Conclusion: If it breaks, I will look for another one...

I received it today, so I don't know if anything will change over time, but the initial impression is very good.
Large and clear screen, with numbers that are easily readable from a wide viewing angle.
The measurements seem accurate, approximately. I placed the main unit next to the external wireless sensor and they showed approximately the same readings. Their difference was about 0.2 - 0.7 degrees in temperature and about 2% in humidity. These differences seem normal to me because I have many electronic thermometers and none of them agree exactly with each other, but they have a difference of 0.5 - 1.0 degrees Celsius, even those from the same company and model.
Initially, I was concerned about where to place it because the instructions said it should be at least 1.5-2.0 meters away from the television, computers, etc., both the main unit and the sensor, which is difficult in an apartment.
It was very difficult at first to find the signal of the external sensor, no matter where I placed them.
Then I read in the instructions that as a solution, I should remove the batteries for 1 minute and then put them back, so I did and it worked afterwards.
Then I placed them in various positions, even next to the television, and they had no problem.
I don't have an opinion on the weather forecast because it will actually start working after about 15 days, but I read that the forecasts from such stations are not reliable, so I will probably use the sensor in another indoor space.
It has instructions in Greek and it is a German company.
If anything changes in the future, I will come back.