I have been eying products that transmit your Ipod on a radio station for listening on your car radio for over a year now. Up until now, the offerings have seemed rather limiting in some way. Either it has been too hard to change the station, the Ipod didn't charge in the car, or the Ipod sat inconveniently on the passenger seat. The Griffin Road trip seems to be the best Ipod transmitter available, as it doesn't have any of these problems.
The cradle system that comes with the Griffin Road Trip is nothing short of amazing. It plugs into your cigarette lighter to power your Ipod while holding the Ipod just where you want it in front of the dashboard. There is a full set of adapters so that it fits all sizes of Ipod. It fits the oldest full sized thick Ipods. It fits the full sized but slightly thinner Ipods (like my 20GB). It fits the Ipod Mini. It even fits the new Ipod Nano. The socket on the bottom of the Ipod plugs into the cradle, leaving the top of the Ipod free for headphones, remotes, or other accessories. The stiff arm on the back of the cradle that plugs into the cigarette lighter is very versatile. It comes with extensions and bends that should be able to fit into just about any vehicle. It fits both my car (where the power plug is under an overhang in the dashboard), and my wife's car with no problems.
The transmitter on the Griffin Road Trip is similarly well designed. There are convenient buttons for changing the broadcast channel, and an LCD display that shows the frequency. Any FM frequency can be chosen for the broadcast, compared to some other Ipod transmitters that have a handful of presets. The buttons for changing frequency are very convenient compared to some other designs that require you to play a short "song" on your Ipod that signals the transmitter so switch channels. The audio quality was very good, certainly better than the reception that I get from radio stations.
The Griffin Road Trip also comes with a USB plug that can power the system from your computer. In this mode you listen to your Ipod on your home stereo. A small module even unsnaps for the cradle system, so that the bulk of the system (like the cigarette lighter plug) can stay in the car.
My only nit would be that when you turn the car off, the Ipod keeps on playing. It would be very nice if the Road Trip could pause the music on the Ipod when the car turned off and the Road Trip lost power. It is just a matter of time before I let the batteries on the Ipod run down overnight because I forget to stop the music.
The only thing that could be better than this system would be a cradle build directly into my dashboard that had a wire to the back of the car stereo. Given the amount of work that would be to install, the Griffin Road Trip system is the best option.