I do not know if the chocolate as soldiers boarding the war had a different recipe, but you can give the current Scho-Ka-Kola to buy because of its stimulant effect. To get here from the effect on her a strong cup of coffee, you would have to eat at least half can (subjectively skin with me as the Ritter Sport Espresso more pure) and a short-term energy boost brings a chocolate with a high sugar content.
What remains is the nostalgia of a chocolate in a can that there is such (or something similar) for over 70 years.