I'd use 'em - at the end of the day these things were made to be used. I have a brand new LC630 power supply sitting in its box, in my closet here in Sydney, sealed and everything...next time I'm at home its going straight into the 630, and its PSU will be replacing the dead one in the 6200. In 2009 I bought a NIB Apple 8*24 card on eBay...it was unboxed and installed in my Quadra.