My experience with wet grinder.
I have a wet grinder (1.5 Lt capacity) and used to grind my Cocoa in it. It was fun at times, sometimes frustrating too!!! The wet grinder generates heat if run for a long time, I mean more than 60 minutes at a stretch. So it was like marathon, taking 2-3 days to finish grinding. And the chocolate was never silky smooth. a bit gritty. I enjoyed the chocolate though!!!!(Almost all South Indians use wet grinder).I feel wet grinder is not a good choice for grinding chocolate.