This is a great podcasts. The episodes automatically come up in correct order so you don't have to hunt for the next one to listen to. One can listen to these podcasts will driving or doing housework or yardwork, so it doesn't feel like so much of an indulgence.
The racial language, particulary the 'N' word, is jarring to the ears, This is something that we can only assume was in general use in the area at mid 19th century. This is unfortunate, but if we can get by it we can hear the best work in American literature.
The whole moral question of slavery is faced by Huck as he realizes that he is helping a slave escape. Twain has Huck philosophically debate the issue weighing his need to see himself as a 'good' person against his loyalty to his friend, Jim. Jim shows his backbone and shames Huck when he treats him badly. Then Huck comes into the company of fellows who really are bad.
Twain also contrasts the wisdom of Huck's creative inventiveness against the 'book learning' of his friend Tom. Huck does not stand up to Tom, as Jim did to Huck.
There is also plenty of social comment on religion, superstition and efforts to reform people.