Oizen's is like a custom Aquatic Mine with random stuff that makes it look like Aquatic Mine, this one is like an import like talking an area from the game itself.
Interesting that Oizen refused to alter his version of the stage to make it more compatible for Brawl specifically because he "didn't want to change the stage at all from its source appearance".
I liked the platform layout of Oizen's better due it being slightly more interesting/unique, but the noclip walls were absolutely a deal breaker, for me. I don't remember Oizen's Aquatic Mine being a let down aesthetically, by any means, but without directly comparing the two I can say I'm more attracted to this version than I was to his when I saw it. (Then again, maybe I'm just biased because Oizen snapped at me when I tried to offer constructive criticism.)
Either way, you did a fantastic job here.