Replay Media Catcher can record flash video .FLV streams and audio .MP3 streams through the RTMP and HTTP protocol. Only 2 programs support RTMP protocol: Replay Media Catcher and FLV Recorder.

WM Recorder can record Windows Media streams and Real Audio/Video streams. It is the most powerful Windows Media stream recorder. It can also download QuickTime and MP3 streams through the HTTP protocol.

Replay A/V can record all streams formats that WM Recorder supports, but it is not as powerful as WM Recorder. On the other hand Replay A/V has lots of features that WM Recorder lacks of: recording Shoutcast MP3 streams with song splitting and tagging, recording from Sirius and XM radio, direct sound recording,...

I would add NetTransport to the list 'coz sometimes it is very inconvenient to record multiple streams from one page. I don't really wanna find all their stream URLs and add them to a stream recorder, it is easier for me to click "Download all ..." and select the URLs I wanna record.

I use all these programs to record audio/video streams. Replay Media Catcher is unique so if you need to record flash RTMP streams you will need it (or FLV Recorder if you like it more).

As for WM Recorder, Replay A/V and NetTransport it is up you to decide which one(s) to use.

I prefer WM Recorder 'coz it is the most powerful stream recorder. But Audio Video Streaming Capture Suite with Replay Media Catcher and Replay A/V could be a better choice for you.

If you have any more questions don't hesitate to ask.