The transmitter works fine as long as there's not a lot of interferance. It works fine in my house, I can't tell the difference between it and plugging it directly in. When I'm in the car it varies from ok to terrible depending on where I'm at like Beta said. If you can help it, you'll proabably be better off with getting a cd player for your car that has input jacks. If you can't find one reasonably priced, you'd probably still be better off just going with one that has a mp3 cd player and burn your music to disks.
Best Method Of Connecting a iPod To your Car CD Player
Is their another way of connecting your ipod to a car cdplayer? Im Kindof Questioning that Belkin FM trasmitter thing, I dont want to spend 50 bucks on it and end up having Radio Sound Quality Instead of MP3. thats the main thing that worries me about it. The Methoth I want to use is a Y Connector. But i havent found many CD Recivers that have a L/R Audio Jack in the Front Pannel. 
