Quality construction with useful indicators. The fact that it takes an external power supply has its positives and negatives. For me as a professional, it is useful because with a power bank I can charge wherever I am without the need for 220 volts. On the other hand, even with a 9V 3amp charger that I have, it takes eight hours to charge two Npf970 batteries and this is called quick charge...! I wonder what it will do with a 5V charger... If you want normal charging speed, go elsewhere, otherwise arm yourself with patience because it will take a long time to charge and you will grow a beard.

It takes a long time to charge (for completely discharged batteries) more than the genuine one. However, it does not have something faster and of higher quality in a duo charger. It does not charge them simultaneously.
Correction: to operate in fast charge and charge 2 batteries simultaneously, it requires a 9volt/2ampere USB charger and not the 5v that most have

Excellent charger and yes it is Pro.
I have been using NiteCore products for about 8 years. I also have the same one but for Fz100.
To work with fast charge, you need a power supply of 9V2A and it provides 800mA to each battery, like almost all chargers in the same price range, such as DuraPro. In single charge, it provides 1200mA. There are of course chargers that provide 1500mA, such as PATONA 1918 Turbo, but I avoid them because they are too much and excessively fast charging reduces battery life. If you want fast charging and don't care about battery life, it's not suitable for you.
-Negatives. You need a mobile charger of 9V2A, such as Hoco (C26), which costs about 5 euros extra. I have the feeling that the second slot charges slightly slower. If you need 5 hours for slot 1, you need 5:20 minutes for slot 2, that's how it seemed to me.
-Positives. You can charge batteries from a powerful PowerBank. The battery life indicator works perfectly for me.

This charger is not pro initially. It is a weak charger that - for me - does not charge 2 batteries simultaneously. It is weak because it is powered by a USB cable and does not have its own powerful power supply. Possibly, if you use a powerful power supply with a USB port, it may save it somehow, but I used the most powerful one I had. It is definitely not a "fast charger". Also, the battery health assessment is not accurate, as it showed a damaged battery as "good" for me. I would return it.