It will take a while for the series to warm up to others and become somewhat popular. I don't expect it to get as popular as the One Piece and Naruto. I excluded Bleach because both the anime and manga has become rather....I'm simply not going to mention it. The manga art style somewhat resembles One Piece, my guess is that the artist is a fan of the mangaka and his work but you'll notice that in the anime version the two series are different art wise. Iron as an element you say? Well instances such as these in anime I tend to ignore it because it really isn't worth the effort to try to disprove something as obvious as iron not being an element, plus, it hasn't ruined the story so in short iron is an element (in Fairy Tail that is) and it rocks. Some people speculate that he is 18, too me he looks 16-17ish, but others think that because he is a dragon slayer that the dragon magic slows down his age. This is because dragons live for a long ass time obviously.
“Pirates are evil? The Marines are righteous? These terms have always changed throughout the course of history! Kids who have never seen peace and kids who have never seen war have different values! Those who stand at the top determine what's wrong and what's right! This very place is neutral ground! Justice will prevail, you say? But of course it will! Whoever wins this war becomes justice!”
― Donquixote Doflamingo