I always do research before making a big purchase, making sure that I'll be getting the maximum "bang" for my buck.
My search for the perfect headphone led me to this: a Grado Prestige Series SR80i Stereo Headphone.
The SR80i has been around for 8 years now but it still has great reviews compared to recent headphones and perhaps most importantly, still appeal to average users and the audiophiles alike.
Top of the line headphones are also known for their expensiveness and this is where the Grado SR80i really shines. SR80i is simply the cheapest headphone that can go head to head with its not-so-cheap, professional grade counterparts.