I had the privilege (?) of seeing this on one of the various extras discs out there. Now, as bad as the Holiday Special is, that has a certain charm to it (yes, even Bea Arthur's inexplicable involvement). But the Donny & Marie thing is just awful-- it's obvious that the staff was like, "Hey, that Star Wars is mighty popular. Let's do something that barely relates to it, and whip up some bad songs and dance numbers!" "Cheesy horror" is an understatement.

I can't even remember how good or bad the quality was-- I think I blocked it out!