Whats a better option 04 Cadillac CTS or 04 Audi A4

Hy im trying to choose a car to buy and I was wondering wich is a better idea an 04 cadillac CTS A/T 3.6 or an 04 audi A/T 1.8T
price range or fuel consuption isnt an issue sin I drive a 2000 grand cherokee 4X4. I like both cars but my issue is the maintenance costs or the problems the car might give me in the future I hope you can help me with this decition based on youre experience thank you.