It's depressing to read a book you enjoyed as a child, and find you don't care for it as an adult. Huck Finn is that way for me.
Huck's endless lies, and the truly interminable "escape" that Tom Sawyer engineers at the end, left me more than cold.
I wanted someone, anyone, to act sensibly. Perhaps that was Twain's point - that most people act silly given any reasonable opportunity.
Your opinion? How long has it been since you last read Huck Finn? Did your opinion change over time?