Quick history lesson. You guys know that backstory saying how this was for the NES and was meant to redefine the platformer genre or whatever? Not true. Check out the games Wikipedia page for more info.
Anyway, let's get this 8 bit party STARTED!

GRAPHICS
Graphically, everything works. Everything has contrast to the background, so you'll never find yourself experiencing a cheap death caused by an enemy blending into the background.
MUSIC
Capcom. 8 bit. Need I say more?
GAMEPLAY
The gameplay is, of course, the key aspect of any game! So how does DVZ stand? First, the combat. The combat works because you rarely, if ever, find yourself standing in one spot wailing on an enemy that takes a lot of hits to die. You often find yourself either killing them instantly or dodging their bullets.
Now, the levels may SEEM open, but you never find yourself lost thanks to the map. You simply need to follow the map and you'll get out alive... implying you can take the difficulty.
This game is HARD. You usually get zerg rushed, so don't get too surprised if you die. A lot. Everytime you walk into a room.

CONCLUSION
This is a pretty good game. A fair warning to you people who need a long game, this game's only three levels long and can be beaten within a day.
However, I find that this game is worth the 500 points it costs.