Having played this game on the original SNES, I had to play it again when it was re-released on Virtual Console. It is one of the best platformers that I have ever played. The controls are solid, the level progression is good, and nothing gets to the point of frustrating. Sure some things are decently hard but you never feel like something unfair.
As a Mario game, it is pretty simple. Get from the start to the finish, collecting coins, and trying your best not to die. The feather power up was the new power-up for this game and honestly, I wish they would bring it back. It is a great item and was really fun to play with.
The story is okay and by this time, if you had played the NES games, you knew what was happening. The music is still memorable and by far the greatest in the series at times. The ghost house theme and others still stay in my mind. The bosses are fun but do get repeated after a certain point.
If you have a chance and have never played this game. Play it. It holds up today and is still one of the best platformers out there. They should teach classes about this game for game developers, to show them how to take a basic system and make a great game.