I still haven't seen Space Dandy. I'll probably get around to it next week sometime. Seen them all, it's kinda neat. The fights, when they happen, are awesome though. I wasn't really into the characters and the story revolved around them. As far as "must watch" is concerned it depends on your taste and what all you've seen. And are you looking for current stuff, older stuff, movies, shows, fanservice, dark and edgy?