I'm glad someone said it so I didn't have to. I love the Metroid franchise. Four Metroid games make it into my Top 50, and two into my Top 10 for the end of the year event we do here. I was born in 1985 and have played plenty of old games. Even with all that, I will say this: The original NES version of Metroid is near unplayable by modern standards. Super Metroid outclasses it by far. It feels so much better to play Super. Light-years ahead.
Yeah, Super Metroid is the better game overall. The only reson I'm able to play Metroid (NES) without wanting to kill myself is that savestates exist. That and knowing the general route I have to follow thanks to having played Zero Mission a thousand times.
I played it without ever using save states (except for saving in the sense of like, not having to use a password to get back into the game), and I can confirm, I wanted to kill myself.