Audi's RS6 Avant is a properly fast car that can haul all of your luggage to a ski lodge in the Alps with ease, while the R8 Spyder can carry little more than a holdall. But both are more evenly matched in a drag race than you might think...
Audi RS6 in-depth review: http://aex.ae/2eDmkP6
Audi R8 Spyder review: http://aex.ae/2dV9ZHl