Sound — 10
In 'Lightning', Metallica's music style has matured alot from the previous album. Mostly because of Cliff Burton's contributions to the songs. His unique bass sound adds a really good sound to their songs. There are some slower songs on this album. Kill Em All was almost 100% fast. But, Metallica can still sound great when playing slow. For Whom The Bell Tolls and Fade To Black are great examples of this.
Lyrics — 8
James' voice has improved a bit, and has matured alot since 1983's Kill Em All, where he sounded rather squeeky and annoying. On this album, there are songs about death (Creeping Death), war (For Whom The Bell Tolls), and other nasty matters. Although, the lyrics are still well written.
Overall Impression — 10
This is Metallica's best album by far. It's much more enjoyable than the last album and has better songs. The highlights of this album are Fade To Black, Fight Fire With Fire (a prime example of the classic thrash metal 'crunch'), Call Of Ktulu (a confusing, but well written instrumental) and For Whom The Bell Tolls (nice rhythm). I would definately buy this album if you like metal of any kind. It's great!