From what I've noticed in several years of eBaying, is that it used to not have any effect at all. As time went on, for a while it had a major impact on older kit prices but that was brief. Nowadays I see small effects on pricing. Older kits sometimes get reduced a bit, just because of the newer availability, but there are still those (and eBay sellers are beginning to notice) that still appreciate a vintage kit, no matter how many issues it's seen, or what value it may hold.