Mario has always been a great series in my mind. I have enjoyed most of the games in the series. It's hard to think of a platformer series that I haven't liked and this is no different.
I have to say that the game is fun. Really fun. The 3D effects are incredibly useful at times. They give a feeling of depth that many 3D platformers have been missing in the past. Sure the gimmick at times is a little much but watching Bullet Bills stream past as they head towards the screen is enjoyable.
Although the main game is rather easy, there are challenging parts. The return of the Tanuki Suit is great. In fact, the game can easily be beaten with just this item. Having two of them almost guarantees that you can beat a level.
I haven't tried the extra levels and I have heard that they are much more difficult and make the game even better. I would recommend this to anybody who wants a 3DS game. If you like platforming, this is a game for you. This is one of the most solid and polished platformers I've played in a long time.