The album from 1981 is their most heavy metal one, although I've always viewed them as a hard rock band. For me this is their second best album (it's better than Hysteria and if the last song on the album was different it would have tied with Pyromania for the 1st spot) with gold classics such as ''Let It Go'', ''Another Hit And Run'', ''Bringin' On The Heartbreak'', ''Lady Strange'', ''Mirror, Mirror (Look Into My Eyes)'' and the instrumental ''Switch 625''. The other songs are very good too. If you want riffs, this is the album for you.