My father has borrowed from me my CTEK MXS 5.0
He uses some cheap charger from Tesco but he had problem to start engine (Peg. 407 gasoline). AKU has still green mark. I was wonder if he needs maybe to replace spark plugs, check wires, etc.
But after he used mine CTEK problems has been solved. His car starts easy even temperature now is lower than before (-15 C in Warsaw Poland
I have not idea if it proof anything but if really use CTEK extend life span of his AKU for year or more it be good saving and environmental friendly solution (I hope).