If adding to the secondary I might try the 4 bars and taste the wine every few days until you get the desired taste. RegionRat you should be fine in an aging wine just monitor the taste. One thing with chocolate is it will overtake the fruit if allowed to age to long. Once it overpowers the fruit the wine becomes more of a "chocolate/fruit" wine not a "fruit/chocolate" wine. I have tasted some other winemakers fruit/chocolate wines and all I tasted was chocolate. At the last Competition I attended this past weekend there was a Cherry/Chocolate that was made using syrup and it was almost all chocolate and received a poor review from the judges, and a Raspberry/Chocolate/Port made with Lindt's bars that was excellent. I work with chocolate in a lot of my wines and the best advice I can give is to TASTE, TASTE ,and TASTE again.