Heck, Sentenced even liked Iron Maiden so much that they put out an EP ("The Trooper") named after one of 'Maiden's biggest hits, which included a cover of the song as the opening title track.
Aside from Judas Priest, the only other real "competitior" I can think of to the type of melodically-driven music that Iron Maiden was playing in the 1980s would be Mercyful Fate, but even 'Fate has a very different, more "evil" sense of melodicism (no pun intended) than what ended up getting used by all the "melo-death" acts of the 1990s and eventually found its way into the music of today's popular "tech" and "-core" bands.
In other words, there's a reason why you can walk into a Hot Topic store today and see a number of Iron Maiden shirts lining the wall:
the band's influence on metal culture, for better or worse, was simply that wide and profound.