It’s great fun. I have attended the race several times in Berlin. Having travelled the world for Formula One races, I intend to do the same for Formula E in the future. Maybe it will come to my hometown of Copenhagen one day (which is a much better idea than the ill-fated idea of getting F1 there).
The first thing you notice is the absence of sound from the engines. But that does not mean it’s not loud. This video explains: