I use the Skip Dr. manufactured by Digital Innovations, which makes several products for disc care and repair (
http://www.digitalinnovations.com). It is relatively inexpensive and does a great job of eliminating scratches that interfere with playback.
No matter how the disc is designed and manufactured, accidents will happen. In the past, I too have experienced problems with a disc right out of the case. I simply returned it to the place of purchase for a replacement, which solved that problem.
By the way, I have learned to give the case a shake before purchasing. If I hear a rattling sound, it indicates that the spindle in the case is broken and that would increase the likelihood of the disc being scratched as it has slid over the broken spindle during normal shipping and handling.
[Edited by paulb_30 on Jun 27, 2007 at 8:02 PM]