I have owned a pair of Superlux HD668B's for a while, reasonably burned in. I just picked up a pair of Senn HD558's on sale at Best Buy for $139. I was expecting the Senns to be much better sounding than the Superlux but to my surprise, they sounded very similar. I am not the type to take something back to a store but I feel like I already own what I just bought. Anyway, was just wondering if the Senns will burn in and sound better?? I am hesitant to do any mods to a new pair of HP's.