In my most recent mailed mileage summary on the Premier update (December 2002) there is an ad for a new “Mileage Plus Gold Class Visa” how is this different from the regular one. The only difference I can see is that you get 2 miles per $1 charged on UA tickets and bonus miles for balance transfers. Is this card worth switching to if I already have the Signature Visa from Mileage Plus? I have to use Corp. Amex to buy my plane tickets but does this new card have any other advantages? I don't see any car rental protection.