If you've got a 3DS, and you've got an Internet connection, there's no reason to not have downloaded the latest system update and pulled down 3D Classics: Excitebike from the Nintendo eShop. It's free, after all.
What can the unique hardware of the Nintendo 3DS do to invigorate the 16-year-old Bust-A-Move (aka Puzzle Bobble) puzzle game series? Based on Bust-A-Move Universe, not much. This is a game that strives to be old-school on Nintendo's modern-day platform.
The minute you start playing Metal Torrent, you're almost done. But the brevity of Nintendo's first DS shoot-em-up isn't the worst of it. My local bank offers more entertaining ways to press buttons and hear jangling sounds.