@nouman: Those two songs you referred to are from the same album, and is a technique called theme and variation. It isn't just some lame excuse to make the song longer or to have more songs on the album.
Also, who cares? Metallica has tons of guitar solos ripped off from several other bands. And I doubt dragonforce did this anyway, you can't just steal a guitar solo without making the backup music have the same chord progression, which is too much trouble to do than just coming up with your own, which they are more than capable of doing. They're also fast, several songs WILL sound the same, that doesn't mean they are. Most bands this fast have no melody, and repeated drum beats and guitar riffs, which Dragonforce does not. It only takes a minor knowledge of music to notice this.
As for Anthrax, I like them, but every song on Persistence of Time is relatively the same, and also sucks.