ehhh... too old school.
Controls are simple, just run, jump and shoot you cannon, like megaman. Saving is confusing and annoying; pause the game, then press down and select at the same times, like putting in a cheat code. Then, it starts you back at the beginning of the level. Why the hell can't it just save, and you stay where you are?
Graphics are O.K. for the Gameboy, but I know the it can handle much better.
No offense to old time gamers, but I've played a lot of old, "classic" games, and I wasn't impressed, nor was I entertained. If the very first games were like this I can't imagine how it got popular, or how it evolved to the great and addictive games with awesome graphics we all see today.
Pros: I guess it's a classic and controls.
Cons: boring, repetitive, mindless wandering, and the "old school feel".