Here's a
link to a previous thread that debated the merits of remastered CD's. For those that don't want to (re)read the whole thing, I've summed it up in terms of discs and sound quality:
Rush Remasters series: an improvement over the originals, especially the 1970s material (2112, Hemispheres, etc)
Rush,
Vapor Trails: TERRIBLE ("overbearing, too loud, distorted")
Rush,
Presto; Test For Echo: also bad due to bad engineering
Rush
R30 DVD: good
Led Zeppelin and Rolling Stones first pressings: bad
Led Zeppelin and Rolling Stones remastered: good
Van Halen originals: good
Van Halen remasters: bad (overly data compressed)
Pink Floyd remasters: good
Here's hoping this thread takes off and becomes a major resource for the board. It certainly has the potential!