I got my main cat replaced at a total expenditure of about $250. Found the actual part online for $100 or so and got my local shop to install because my Contour buddies around here were tied up. The precats are a lot more complicated, sure, but IMO since you're not getting the work done under warranty, I'd say screw "dealer care" since I rather doubt they care much about giving YOU the best deal. Shop around.

"Think of it, if you like, as a librarian with a G-string under the tweed." Clarkson on the Mondeo.