I got the coupe, but my deciding factor was the ease of loading a wheelchair in the back. With the coupe hatchback style it opens wide so that the frame can be fitted into the back without any problems.
On the cabrio the rear-upper section just lifts a small amount that would increase the difficulty of doing that.
Also the cab has a smaller rear window, decreasing visibility to the rear somewhat.
I'm happy with the coupe, but would have gotten the cab had the wheelchair not been an issue.
You're lucky that the dealer has some in both models that you like. GO FOR IT~!
