That's your opinion, don't you see? You think you are fine, well, so do they. You posted your own videos, someone else posted theirs, they aren't here to answer any questions, they aren't here to take or refute any comments/criticism, we are talking about them behind their backs. Their video has been posted up with 'oh look how funny these guys are', would you be happy if that had happened to you? If you consider their opinion to be wrong, say so by all means but you cannot say their opinion is a slander/libel just because you don't like it.
A critique of their techniques would be in order but ranting because you think it was a personal insult is just plain doolally.