Personally, I found the Z to be OK in stock form. I was very very disappointed with the handling. I have since installed larger sway bars and have coil-overs. It is accepable now.
On the power side, I am not HP crazy. 300+ HP is more than what I need. However, as others may have already know, power delivery is not as linear as expected. This could be the tranny, the computer, the throttle-by-wire, etc. or a combination of all. So far, having been a member of this forum, I have yet to see a final fix to this issue. Bottom line...."Power is nothing without control." VDC is way too sensitive reducing the fun-factor. VDC can be turned off obviously.
I am an easy going person. I did notice the paint quality but it was a non-issue for me. My engine was replaced and that did not bother me. I have hit 260 temp on casual and traffic days, but have not encountered the limp-mode. I have not gone to Las Vegas yet, so it might be a let-down when I do go to Vegas and be in limp-mode
As others have said, if you are a straight-line person, the Z is not the car. My car is a daily driver, so straight-line is at the bottom of my list.
I still love the Z and she may be a keeper. However, I am itching for a black Roadster. I may stop by the dealer again today to see if I could get the same deal as our Canadian member, R6????-something. I am in California and my ROI off a cab could be well worth it.