I grew up in the woods, saying Porsche one syllable until NFS 5 came out and I heard it said Porsche. I still missay it at times, but get it right more often.
Typicly if someone asks what I drive without seeing it, I say a "modified Volkswagon", or something along those lines.
I've also had vette driver next to me go "Nice Ferrari, what kind is it?". Just after saying it, he looked down at the sides of my car with PORSCHE accross it - serious *oops* look on his face - priceless.
There are all sors of people, I try to be nice to all. The fact is, not everyone just automaticly learns things, sometimes they find out by experience. For example, until meeeting a M3 owner two years ago, I couldn't of told you much about a BMW M3.