MiBoxer C4 charger


I was expecting the MiBoxer C4 to be a 4 battery version of the C2-3000, which is an excellent charger, but it is very different.
Here are features the C2-3000 has which the C4 doesn’t:
Calculate % of charge
Calculate time remaining to full charge
Automatically adjust charge current to match internal resistance.
Seven manually selected charge currents (only 2)
1.5A maximum charge current (800mA)
Display capacity and internal resistance of all batteries (only shows this information on bay no. 4)

Here are what I consider are some problems with the C$:
The display doesn’t match the actual current or voltage:

It never reaches 4.2v when charging Li-Ion batteries. Typically it will reach 4.17v, then when the charge current stops, the battery voltage drops to around 4.15v, but it starts to discharge relatively quickly, and within 4 minutes, the voltage will drop to 4.11v.

The actual charge current was:
Single battery Low: 350Ma
Single battery High: 790mA
4 batteries Low: 340mA
4 batteries High: 740mA

Here are the manufacturers specifications:

And here are currentv voltage graphs: