It is hard to complain about the lack of an original Mario game on GBA when it has ports this good.
The gameplay here is simply excellent. The controls are responsive, graphics are artfully cheerful and the soundtrack contains many classics iconic enough they will sometimes be recognizable even to those who have not played the game. One added element--or really an element much more developed from Mario 3--is that the main storyline is pretty easy to breeze through if you just want to see the ending. It does get tough towards the end but the real--and optional--challenge is to find all the many extra levels and secrets throughout the game. The gamer has the option to spend as much or as little time as he wants on these things and this makes the game work quite well for gamers of a variety of levels of commitment. Playing through this, it is easy to see why this has been an element of every Mario game since.
It does suffer somewhat in the translation to GBA just slightly though. The biggest issue is it has lower resolution than a television screen so there is an occasional blind jump or dastardly off screen enemy where it feels like their should not be. Mario does have the ability to look around though (which scrolls the screen from the gamers point of view) and that mitigates this already minor problem somewhat. There is also the fact that you can save whenever you want and don't have to beat a special level to do so like you did on the SNES original. This is an absolutely wonderful feature in a handheld game but it does through off the difficulty curve somewhat, making it a bit easier than originally intended.
These small complaints aside, Super Mario Advance II: Super Mario World is highly recommended for anyone who does not hate platformers. There is really a little something for everyone here. Newer gamers and long-time Mario fans will enjoy either the history lesson or nostalgia trip whatever the case may be. And not just that--this game is just plain good no matter how you look at it.