Any Experience w/ Brand X FM Transmitters?

Question

I have 2 different Brands and types of FM tranmitters that plug into the bottom connector of my iPhone. They were advertised to work with both ipods and the iPhone.
Alas, the music keeps playing on the speaker and doesn't transmit. The charging part works though.
Has anyone else had any positive or negative experiences with this type of transmitter?
My 3rd older one that fits into the hadphone jack works fine.

Answer 1

I went to the Apple Store and they told me that there wasn't a cord that would allow me to play my music from my iPhone to my car stereo.
So...
I bought an iPod because I wanted my music in my car.
I also bought this Kensington Digital FM Transmitter/Auto Charger for my iPod as well. I found a radio station and it worked perfectly.
I thought to myself, why not try to hook my iPhone up to that cable and see if it worked.
Well it did and so I took my iPod back and now am able to use my iPhone in my car using the Kensington cord!!
Here is the link to that cord:
http://store.apple.com/1-800-MY-APPLE/WebObjects/AppleStore.woa/wa/RSLID?mco=F92 F7BFD&nplm=TD145LL/A
It just goes into your cigarette lighter and then you set a radio station on the cord and then tune onto the radio station on your car.
Hope that helps,
Sam
P.S.- Your iPhone is going to tell you that the product is not compatible with the iPhone and would like to know if you want to put it into airplane mode.
Well just select "NO" and then your phone will work like normal and play your music through your speakers and it will still be able to receive calls while listening to your music, the music will just fade out while you are driving and allow you to answer your call and then once you are done, continue playing your song right where it left off.