yeah i got a cable pretty much identical to this for about £3 on ebay. Russ andrews are sadly the kings of over-charging massively for very basic things. It will indeed be an excellent cable, but in a car, i question whether the sonic benefits of a cable of that type would be noticeable.
Also the russ andrews one doesnt let you charge the ipod:
http://www.ebay.co.uk/itm/170818445498