2010 Audi R8, S4, S5 Cabriolet. Audi has a rich performance-car history, but recently the brand has stepped up its game. Need proof? Look to the R8 which garnered praise when it was introduced for both its performance and stunning style. Helping silence critics who called for more power, Audi is introducing the V10-powered R8 5.2 for the 2010 model year. In this video, Kelley Blue Book heads to Infineon raceway near Napa, California to sample the 525-horsepower R8 5.2 as well as its siblings, the supercharged 2010 Audi S4 and S5 Cabriolet. For more new car reviews, interviews and automotive news visit http://www.kbb.com today.