In reply to ian bryant:
I have a Fiamma one on my Vivaro and i really don't like it. With Mountain Bikes i struggle to get them lined up with each other without rubbing. The arms it came with were funny sizes and after only a year most of the red plastic components have started to bleach out (and i live in Wales so it wasn't like it was sunny).
The attachment system seems a bit week and on the Vivaro the stabilising arm puts pressure on the rear window and i am sure it will implode one day.
Sorry it is not a recommendation but i would think twice about buying this particular one again.
I will buy a Thule tow bar mounted one next time.