I have paddles and they are not "instant".This means there is a lag ,when you push the button there is a lapse of time untill you are in the next gear.I've heard that the 08 are better tuned therefore shift "faster".Downshifting seems to be much quicker into the next lower gear.
I personally don't mind it since I also own a Merc CLK 430 and so I am used to the little "lag".I enjoy the vette's shifting better.
I would prefer to have much sharper shifts at full throttle.I believe that you should shift about 500 RPM before the actual RPM you want.I don't know the exact difference in RPM or milliseconds between the manual or paddle but I do believe they are close.
If you like the "feel" of manually shifting,the paddles will never be good enough for you.
I have owned manual cars(RX7,Escort GT,couple of Hondas),but I wouldn't ever go back to a manual.I do believe the new automatics perform better than ever.I enjoy the option to control the revs,yet,having the car in "drive" is great in traffic and on days where you just don't feel like shifting.IMHO I think you get the best of both worlds but that's just my .02 ($CAN) which by the way are worth more than the .02 (US$) these days...

......:cheers: