The comparisons to the Vectra are a little off the mark. The Aura and Vectra share basically zero components, they only share similar front end styling. The Vectra is on a shorter wheelbase version of an epsilon 2 platform, which is totally different that the LWB epsilon in the Aura, not to mention different engines, transmissions and interior. It seems like drawing comparisons to the Vectra is generating a lot of good press for the Aura, but I really can't understand why as I really don't think that the Vectra is a very good car. It is overwhelmingly sold to fleets and its generally thought of a rental fodder or as a company rep mobile. I rented one in Germany and it is loud, rattley, and underpowered. The Aura has it beat in every category except maybe body control.
The old Saturn L series was far more closely related to Vectra (albeit the older version) than the Aura is, and look how that turned out.
