It has been a long time since the last time I've played. When I was like 13, I've always said that this was a good game even though I understand why some people disliked it, but replaying now I'm not so sure anymore

The music are awesome and the sprites are very well done. Not only that but every Kaiju fight is awesome (for an NES game, obviously)
The problem unfortunally cames when you play the side scrolling stages, which is basically 80% of the game at least. It's almost impossible to dodge any obstacles with Godzilla, but even considering that those stages are easy as fuck, specially with Mothra (which is funny because she controls like ass)
But here is the bad part. Is not just because it's easy, but because it's boring. After Mars or Jupiter, the game doesn't add any completly new stage (at least visually), and when it does it's just an color swap of another one. The only times I've lost Godzilla or Mothra outside an Kaiju fight was just because an "Bomb" kept hitting me because the game doesn't have invencibility frames (neither for you or the enemies)

I wouldn't say to play it, but I wouldn't say to not play either. Although It's repetitive after sometime, it's short and does provide some fun moments
It's mid, no doubt. But at least it's closer to being good than to being bad