91 octane?!  I beg to differ!  VW engines were built to handle cheap low quality gas all around the world, like in places where they say "octane?  what the hell is octane?" (usually said in a foreign language :) ).  I've always run my VWs on el cheapo 87 octane gas with no problems, no pinging, etc.  Anybody that puts 91 octane in the tank of a VW is just burning money, in my opinion.  Of course, in the event that I am wrong, someone please correct me!

Sean