I agree with all you previous writers. The banters make it easier and motivating to keep on learning Japanese, although it sometimes does get annoying if one wants to listen to only the dialogs for practice.
I think a good idea would be making the episodes in versions with and without banters. And why not a version with chatter in Japanese only, since listening to Japanese explanations is a good way of learning alternate ways of saying the same thing.
And one tip for listeners here is to try EnglishPod101 too. The dialogues are of course in English (surprise surprise!)
but all other talkings are (mostly) in Japanese. Also it's quite interesting to hear what Japanese translations would be likely/suitable to spoken English expressions one hardly finds in traditional academic textbooks of any language, as far as I know ("I got it", "aw, get on!" etc)