I'd say probably the most oddball thing is that Luigi is a completely different person than he is now. To be fair, Luigi at this point in the franchise was no more than just "green Mario" and didn't get his modern personality traits until the American Super Mario Bros. 2, so he was pretty much a blank canvas. That being said, he bears an uncanny resemblance to Wario in this OVA; he dons primarily yellow, not green, and more importantly seems to prioritize riches over his own personal safety.
The animation is a little rough but it's perfectly serviceable, and the music tracks, albeit repetitive since they play so often (especially the opening theme), are good. The use of sound effects from the games is a cute touch too, and there's even some arranged versions of SMB1's music!
If you like the Mario games, it's well worth the roughly hour-long watch, even if at the very least to see how far we've come with the Mario series. Heck, watch it with some of your Mario-enjoying friends, they might get enjoyment out of it too!
