provided your factory fitted head unit which am assuming you have has a CD changer output, you will be enabled to use the fitted ipod interface being one of the top 2 on that list of 4 from your link.
but chek with your manufactered head unit 1st for compatibilty.
they are worth getting for those users that want to keep the stock radio. and it also enables you to use the OEM interface of the radio to control the ipod.
Unlike the FM modulators which functions via "radio signal" only and can only be edited in terms of changing track via the ipod only.
Hope that helps:-) And for those that i'v fitted and have worked sufficiently, the users have been mor than happy with them so i cant realy fault the kit one bit. Connects 2 are definately mor reliable for wiring interfaces than Autoleads are!