Alright, I got my code today! Played through it once.
Tip: Do not play on Easy! You get Achievements but don't unlock characters, which are necessary for another Achievement.
Bad news: second player doesn't earn Achievements, in local multiplayer, anyway. Hopefully that doesn't apply to online games, but I have not checked yet.
It takes about 1.5 hours or so to run through Story mode, but you'll need to replay it multiple times to see every stage, character, and ending. The game is a bit old-fashioned in some ways, but it holds up great overall.