I have only used this a few times but can safely say that it charges my I-pod touch and my Blackberry (with Blackberry compatible USB cable) at the same time perfectly well, which is exactly what I bought it for so all in all I am very happy with this product. It comes with an I-Pod USB cable so if you want to charge any different devices you will need to get hold of the correct cable, but this is fair enough. Product itself feels decent quality and has a nice gloss black finish to it.
Does the job and being able to charge two items at once is very handy. Not the fastest charge but As long as you remember to connect it as soon as you get in the car then it works fine. The lead is long enough to position your phone pretty much where you like in the car.