I loved my MG111A's, but I have to admit that they went bad after 9 years of med. to heavy use. By heavy use, I don't mean high power, just lots of playing time. They don't have voice coils to go bad or surrounds to rot, but, what they all will eventually have is a problem with the voice coil de- laminating from the mylar panel. So, the wire grid is being moved by the signal/magnets, but it is not moving the diaphragm itself. I could hear the wire grid drumming away on the panel during play. When I disassembled mine to repair them, I found the top and bottom 8 inches of voice coil wire was no longer attached to the panel. For this reason, I would never buy a used pair. I still like Maggies though and would even buy a new pair some day if I was willing to give up the space to get the most from them. I never had any trouble with the "delicate" true ribbon tweeter and I would expect the newer Quasi- ribbons to be even more durable.