I bought the 100's off ebay so no warranty and the cabinets are beat up a little having some scratches and a little splitting at one corner. I would be able to put the extremis in without making any changes to the cabinet that would make it unable to go back to the origional drivers. I guess I will just have to get replacement drivers then probably cheaper than the extremis anyway. I wasn't planing to change the built in crossover either just wondering how the extremis would match the one in there. These are v.2 so were talking about 4 woofers not 6 and it has to be the driver making the rattle it's not only happening at peak volume it's just most noticeable then. It can be herd across the room sometimes when playing at peak volume about 105 db but only on certian notes.