Even in games like Super Mario world, You will still have trouble just running flying at times

Super Mario Bros

It’s true that the D-pad is clearly circular, but for the games I’m playing (super mario, donkey Kong country

I played Super Mario World with it and it worked just fine.

Also I actually died falling off the very first vine in Super Mario Bros. 2 in the all stars collection

I'm not sure whether or not the D-pad is more sensitive than the original controllers yet; so far I've only played Super Mario 2 on the Super Mario All-Stars cart with the new controller.