I dropped Kanpani Girls once FKG went online.
There were some aspects in KG I liked, but the rest like 70% were mundane and quite bad when compared to FKG.
Same with drop rate and Character acquisition. In FKG there are events that net you a solid (slightly weaker, but still good enough) 5* characters, one after another.
In KG the best thing that would happen to you would be stupid events that allowed you to forge lame Event weapons, and events that would give you a gold mail box, that did Jack sh*t for you anyway.
I am really glad, how FKG turned out, many of the mistakes that have been made in KG are not present in Flower Knight Girls and the game itself feels more natural with its progression and player rewarding.