My only concern with the convertible is the added weight that will come with it. I mean, the CR-Z is already kinda heavy for what it is, and the added weight to make the body more rigid won't be a good thing towards performance.
Anyways, (not directly related to the topic) I just stumbled on to this photoshopped CR-Z and wanted to share. Click the image for source.
I kinda like the Scirocco-ish widened rear end.