The Aston Martin DB9 is a two-door, four-seat luxury coupe that gets the Volante surname when it's transformed into a convertible. Introduced in 2004, the DB9 had a near-death experience before the 2013 model year--but it's now back and refreshed, still the grand-touring leader of a lineup that includes the two-seat Vantage, the four-door Rapide...