"Quite possibly the best heavy metal song ever."  Or at least one of them, certainly one of the Accept's finest. There's no weak link in this song. :) Metal Heart also happens to be my favourite album.
"Metal Heart sounds strangely similar to Metal Gods.."
No it doesn't. Not remotely. Lyrically and musically they're worlds apart. Other than being high quality, top-knotch HM tunes the two have very little in common. Just be quiet and enjoy the metal masters.