Sony Ericsson W810

I was wandering if anyone has tried using the monster cable wireless fm transmitter. Using the FM transmitter, we should be able to play music from our mp3 player and hear it through the stereo in our car. AND it plugs into the cigarrette lighter, so if could even possibly charge the phone as well. Someone let me know if they have used the transmitter. The model is MPC FM XMTR. Thanks