Obviously VLC player and MPlayer just dump streams while playing them, so they provide real time recording only.

Other choice is very very limited. ASFRecorder like software can record Windows Media streams through the rather obsolete MMS protocol. They should work faster than in real time... but it doesn't really help a lot.

Capturing/ripping/downloading media streams on Mac OS is a real headache. One is lucky if he/she can capture/rip/download in real time. IMHO Mac users are doomed to use Windows with bootcamp or Parallels Desktop for Max OS X.

This is not that bad. Parallels Desktop allows you to run Windows applications from Mac OS X smoothly. Replay AV is one of the programs that was tested on Parallels.