You can go for the one you linked to which includes a Y cable that goes from the cigarette lighter socket to the PDA then to the receiver or you can get the one @
http://www.totalpda.co.uk/TomTom-Car...iPAQ-4150.aspx which is a moulded cradle which comes with a power cable from the cigarette socket to the cradle which has the other connections built into it....and yes you can connect your TomTom receiver directly to both of these. The reliability is pretty good and is much better now than when they were released as TomTom keep improving on the design.