I noticed current mpc-hc consumes CPU *continuously* when the video is paused, it can use ~5% on my Athlon 64 FX (2GHz) machine or ~2% on my laptop (Core 2 P8600). BTW, the video I played were RMVB and MP4(AVC/AAC).
Windows Vista comes with symbolic links functionality, but 7z always read them as zero-length files. It should either follow the links or store the links as is, but I think in Windows platform following the links is preferred.
http://en.wikipedia.org/wiki/NTFS_symbolic_link.