I ended up with a error message when i connected one of these, it wouldnt clear and the radio had to be changed under warranty in end. I didnt try fitting it again...
I found that the connections on the back of the bead unit are the same as Blaupunkt so used a £9.99 Blaupunkt aux in cable, but you can buy a Blaupunkt iPod connector which plugs onto same port which also charges it. This is what the Alfa owners use on their OEM HUs but it's muchore expensive at £50ish iirc
To add I've used the aux cable one on both my original HU & my upgraded Cabasse HU with no issues.