I had vertical doors on my Camaro for 2 years. I loved how it looked and the amount of attention it got, but it was a BIG pain in the ass. It was hard to get in and out of because you could only open the doors normally about half of the way. You also had to shut the doors a lot harder and have them realigned every couple of months. AND you had to explain to each person how to open and close the doors properly.
So even though I loved the vertical doors when I had them, I would NEVER get them again.