For a sedan, the cargo space in the A4 ain't half bad. Cargo space in the Volvo S60 is 13.9 cu.ft, it's 13.1 in the Volvo C70, and 13.4 in the A4.
To each his own, it all boils down to personal taste. Had the Avant (Audi-speak for wagon) been available in April, we would have brought one home due to its queen-size cargo space. We purchased the A4 because of it's awesome exterior and interior styling, 4-year bumper-to-bumper warranty, 4-year free servicing, renowned quattro all-wheel drive system, tunability and reliability of the 1.8T powerplant, and price (more bang for the buck than the bimmer). A lowered wagon with nice wheels sure looks nice...