I am looking at renting a car in one of the German airports doing a bit of exploring in some of the German cities before heading to Switzerland, then on into Italy, before going through Austria and back into Germany.

The last information I found was from 2009 where I could not drive a BMW, Audi, Mercedes or a convertible into Italy. Are there other country restrictions?

Is this still the case of what car rental companies can I rent from with no issue.

My only requirement is the car has a bit of shove, I have no interest in touring around europe on a Ford Ka! I am aware of the need for the Vignette in Switzerland.