I never cared because it was still them playing the music.
You need to buy the remaster of Unleashed, because it contains all the cuts left off
the original album (Delivering the goods, Starbreaker).
"Killing Machine" was the UK version of the album.
"Hell bent for leather" was it's US name.
Apparently, the US market considered "Killing machine" too extreme a title, to be stocked
in K-Marts, etc.