Both are awesome cars with great potential when it comes aftermarket goodie time. But my thoughts are the Vette will do one thing awesome and that's going in a straightline with some decent handling and overall performance. Where as I see the Z as an all the way around decent performer with the capability of being a track monster given the right mods. Either way in this situation you can't make a wrong decision. Get what will cater to you the most and what you will have the most fun with. good luck