Okay personally I use the ice-link system that is hardwaired into the cars system (mapped to the cd shuttle button). That way I can control everything from my steering wheel, it’s about R2000 installed.
The iTrip and similar unpowered FM transmiters suck. They suck bad.
However, while my car’s been geetting fixed I needed an alternative and went for Griffin’s RoadTrip (R550, WW computers, Cretsa). I’m blown away by how good this unit is, really blown away, so much so I bought a second one for my wife. The trasmission to FM 88.1 is perfect and it charges too.
If you want the sexier option, the icelink rocks, but having said that, I have found no fault with the RoadTrip.
Hope this helps…!