first of- if you own a gamecube and dont have this game, then you've been missing out on a masterpiece. this game is as close to a perfect game as u can get.
graphics- 9.8 The graphics in metroid prime are some of the best graphics I've ever seen. i havent even seen one glitch yet.a really great special effect is that sometimes you can see a reflection of samus in her suit. overall- the best graphics on a game yet.
sound- 9.3 Not a high point of the game but the sound is great.
gameplay- 10 This is where the game really shines. theres just so much variety in the game. u start out with only one beam called the power beem. But as u progress through the game u will earn the wave beem, the ice beam and the pasma beam (the most powerful one). you also get suits like the varia suit the gravity suit and the phazon suit, which comes with its own beam. you also get different vissors like the battle visor(the normal one) , the scan visor, the termal visor and finally the x-ray visor. another cool feature is the morph ball.
overall- 9.8 this is the reason why you should own a gamecube.