I have one of these cheapo magnetic ones in each of my cars for both phone and sat nav...

http://www.ebay.co.uk/itm/UNIVERSAL-MAGNETIC-MOBILE-PHONE-CAR-HOLDER-HANDYCLICK-MAGNET-BLACK-BRAND-NEW-/140917937582?pt=UK_Holders_Mounts&hash=item20cf5d15ae

I bought three so have one for each car and enough plates for both my phone and the wifes and the sat nav. On two cars they are stuck to the dash but in the Octy I've butchered another vent mount and stuck the vent clips on the back so it uses the central vent which is more than man enough.

These Brodit combos look ok but at almost £40 for the 2 parts.... AM out lol