Next Towcar - SUV or 4x4 Estate ( Outlander v A4 )

Having worn out my very steady Hyundai Tucson I am looking at a change of car. I do lots of motorway miles with work each week so thoughts of increased comfort and economy are drawing me away from another SUV. Saying that Ive a good deal offered on a nearly new Outlander GX-4 ( 2.2ltr) but am sorely tempted by an ex demo Audi A4 Quattro. Both will pull my aging but well loved Elldis GTX Typhoon but Im now worrying if I get a newer van in the next few years whether the Audi gives me less options towing weight wise. Anyone any thoughts/experiences. Im new to the forum and this is my first year caravaning.