I would have to agree, a Porsche may have parts from VW or Audi, but it really is the build philosophy and the driving experience that makes it a Porsche.
My next Porsche will be a 914 (can't afford a 911 yet), my 944 is a blast to drive, but I'm proud to say that my first and favorite Porsche is my aircooled Vanagon. About as close to a 911 as you can get!