I have used the ECM-CS10 stereo microphone a few times, in different scenarios, and I have to say, this is a very robust and easy to use Microphone. I have used it for online chat and found that it was extremely clear, with very little background noise getting through. I have also used it for recording other people in large, studio-ish rooms, where good microphones are a must in order to reduce echo and other annoyances. Again, it performed admirably, picking up the users voice very clearly.I have also used this mic as an attachment to the Sony HDR XR550, when footage with sound needed to be shot, and there was no room for a large boom microphone. Again, it amazed me with it's voice clarity.
The only downside I have managed to find with this product is that they seem to be very fragile. I had purchased a few of these for use with multiple cameras at the same time, and when removing them from their somewhat safe storage area, I had found that one had mysteriously shattered, and another had lost some of its casing.
Many microphones such as this one can cost a small fortune, but for around £35, depending on where you shop, you can get an excellent, high quality product for just a fraction of the price. Just make sure when you are transporting them, you keep them very safe!