As bizarre as this movie is, and how controversial the whole flying thing is. I just watched this movie again for the first time in a while. And after watching every Godzilla movie before it the previews days I gotta say, from a technical standpoint Hedorah is really fantastic.
I'm pretty sure there is zero stock footage which is a big deal for a 70s toho scifi movie. The atmosphere created is completely different than the island themes that we had been treated with over the past few installments.
And other than the actual flying puppet, the effects are far superior to the previews two or three films, and head and shoulders over what we get until mechagodzilla.