I actually love this episode! Of all the bizarre not-so-super heroes Prince of Space is one of the oddest. I especially love the riffs about the uselessness of the aliens' attacks ('I refer you to my earlier codicil regarding the innefectiveness of your weaponry...' or something similar). Although it's not as good as this episode, I think Invasion of the Neptune Men is also pretty funny, so you may enjoy it after all.

Regarding the barbed comments, some of it gets a bit intense for me here... but this is true for me in any of the foreign-made films in the later years, from Jack Frost through Gorgo to the Final Sacrifice. Too often the national stereotype jokes are merely tired cheap shots; Best Brains could do so much better, I don't know why they settled with that. Maybe it's a midwest thing?