So has anyone installed or looked at installing one of these yet?

Dice i-Audi-r Audi IPod Integration Adapter w/ Auxiliary Input (http://www.amazon.com/i-Audi-r-Integ.../ref=de_a_smtd)

I was looking at this as my A4 did not come with one and am curious what others may have experienced with it or if they were satisfied with the factory model. Also does anyone have any advice on what one should get if they currently do not have this option.

Thanks.