Definitely the N64. I have two little brothers and the controllers just won't stop breaking. I've thrown a bunch out, have one where the R-button is smashed and can't be used, a third-party one that doesn't work for no reason, and others. The contol sticks are super-shitty....Mario Party and Paper Mario both had parts that required you to spin the stick as fast as you can (AKA break it), so at least one controller has been lost for each game. Even if you avoid those games, the sticks still wear down and become loose over time.