This is my first post here. I own a pair of Bose OE and have been fairly pleased with them. I'm am considering buying a used pair of Grado SR-80i for $65. The owner has done some modifications, though. He has replaced the black screen with a silver one. He put dampening felt on the inside, vented the drivers and took the mesh off of the inside of the cup. How would these modifications affect the sound? Is it worth it to buy these headphones with all of the modifications made? Thanks for the info.