Hello...new user here. Very brief background - I got interested in the StoryCorps concept and before a visit to my parents decided to purchase 21st century recording gear. After some research, I purchased an RH-910, an MS907 mic and a set of V500 phones plus some discs. The experience worked out very well, and I have uploaded the PCM recordings to some DVDs for backup. I plan to do more of this with my parents and my wife's parents, but have a question I would appreciate your help with. I did the first set of recordings in PCM. It seems that the only drawback is that PCM has a relatively short recording time per disk - is that correct? If I use Hi-SP, or even Hi-LP, for these voice recordings, am I likely to notice any degradation in sound quality? Are there other disadvantages for editing or backing up to other disks? Many thanks J. Newell