C6 Z06 with 355/25/19's on stock rims all day.
To me the caddy is just another daily driven car you see on the road everyday and will look dated just like the previous V. A properly done Z is a more special car that gets taken out when you really want to enjoy life and shouldn't go out of style thanks to its amazing sounding NA 427ci LS7 banging gears at WOT. It's real man's car compared to a CTS coupe especially with an automatic.
The C7 Stingray is nice and all but only traps 117mph and is about 300lbs heavier then a C6Z.