How well did it do in the theatres?

I consider myself a kaiju geek, and I've seen much worse than this. Compared to the mid-1960s Godzilla and Gamera films, it comes off a lot better, FX-wise. As popular as giant city-stomping monsters were, I'm kind of surprised this never became a franchise, unless it flopped badly on release.

"You may have come on no bicycle, but that does not say that you know everything."