I’m thinking about buying two pairs of these off a friend for dirt cheap, but I want to know if they are any good or not. He doesn’t have them hooked up so I haven’t got a chance to hear them, but they're in brand new condition. Any of you guys or gals have any experience with these? Are they at the very least an improvement over factory? I have a factory head so I doubt they'd make that much of a difference but if they're any good I’ll give them a try.