SEE THE FULL COMPARISON STORY: www.edmunds.com Corvette Grand Sport Road Test: www.youtube.com SEE RHYS MILLEN TOP PIKES PEAK: www.youtube.com It's already hot at 11 am as we pull our 2009 Nissan GT-R into the visitor's parking lot at GM's proving grounds in Arizona. The Japanese supercar looks like a spaceship next to the aging, 1960s-era brick buildings that front the massive desert test facility on the outskirts of Phoenix....