Best way to play Super Mario World, hands down. It improves somethings and Luigi adds even more replay value. People make such a big deal out of the screen crunch, especially when in-game Donut Plains 3 brings up camera controls. Dare I say the SNES version's overrated and is only good for 2 player.
It's not as good as the original classic (inferior music, lowered difficulty), but this serves as a nice alternate version. Giving Luigi different attributes than Mario is a welcome change. The results screen that tracks your progress is really cool, and I like the incentive to collect all the dragon coins. Overall, a good port/remake.
This game does what the other truly great Mario games do, give the player joy through variety. Mario jumps and does some other stuff if he has power-ups or Yoshi, and all the gameplay toys with that. The key I think if that the variety here is a just a bit broader than others in the series. It slaps.