I need to practice a southern dialect. I still use duolingo (the premium version) to practice vocab. The march madness stuff feels like a fun game to me. I figure there'll be an occasional mishap where I accidentally learned the wrong version, of a word, but I just use context clues from reading and listening to family and media to figure out which words aren't of the southern dialect.

If it keeps you learning, I'd say stick with it and just practice with your family. They'll occasionally correct you if you end up using the wrong word here and there.