So I shouldn't be hesitant to buy used headphones? I understand and have heard that headphones actually increase in sound quality after prolonged use but you never know if the previous person took care of them or not. Maybe I am just paranoid buying used products over the internet.  

I am new to the whole high quality headphones , yet I am very excited to get into this world and potentially be an audiophile. My first purchase was the Superlux HD 681's, which I like very much. I plan on slowly increasing my collection of hi fi headphones.     So my question comes in, I...