Traded my 2000 silver/gray Coupe on a 2002 QS/bk Z06. My neighbors didn't even notice that I got a new car.
The interior noise was lower in the coupe.
I liked the ride quality of the coupe better. It could do everything I asked. The Z is a little stiff for the roads around here as a daily driver.
I modified the exhaust on the coupe by cutting off the stock outlets, drilling the internal muffler baffles, and welding a 3x5 inch 90 degree ell on each muffler. WOW, great sound - deep angry growl - better sound than the Z! If I can find Ti ells I will do the same modification to the Z.
All that said, I wouldn't trade the LS6 motor's top kick for anything. It gets the R's so fast I have trouble keeping it out of the rev limiter in the lower gears.