WSR, Windows Speech Recognition, was not designed with a Bluetooth
Speech Model. What is worse is most Bluetooth sample at 4 KHz while
WSR samples at 16 KHz. If you make a Windows Sound Recorder recording
(Start button, All Programs, Accessories, Sound Recorder) the playback
will be electronically dirty.
There is a new VXI Bluetooth Xpressway model that samples at 16 KHz
but is still not as good as a good cabled headset or a good wireless
RF microphone.