This was a fun game to play; first by rental, then by way of owning the game. Even those who haven't played a single Kirby game before can easily pick up on the controls, which are easy to learn.
Each game has it's own unique element. The first game is based off of the first Kirby game, the second game also has a few levels with more of the game's abilities, the third game requires you to find up to 60 Treasures (which I have done), the fourth game is unlocked after clearing game two or three and each level has a time limit, and the fifth game is unlocked only after clearing games 2, 3, and 4. In addition, you have to use a different style of copying abilities called the DX Copy, but once you collect that DX Copy ability, you can use that ability for the rest of the game.
Clearing that game unlocks a special boss challenge where you have to defeat all 19 of the game's bosses, and there is also a food-based race game to go with two other minigames as well.
As I alluded to earlier, the controls are easy to learn and flow smoothly, and some of the bosses can be a challenge, but they sometimes move in patterns that can be learned and eventually predicted. Even so, some of the bosses can be quite the challenge, especially Meta-Knight.
I would definitely play this game again; anyone who is a fan of Kirby should definitely own this game without a doubt.