Pre-production discs (betas, prototypes, debug, etc...) are often very expensive, but interesting work-in-progress snapshots. While their costs are often prohibitive, it's great to preserve them whenever possible.Perhaps due to rarity, these discs are often hoarded and not shared. Unfortunately as they are printed on CD-R they are also more susceptible to disc rot. The top two discs were preserved, the middle disc was only partially preserved due to disc rot damage, and the final disc is currently at a top-notch cd cleaner / resurfacer who is doing his work to get a perfect dump... fingers crossed.