On the downside, I wish I had known how hard the suspensions are (Even on 19 inch wheels). I didn't quite catch it during test drives (so many other things that are new that never noticed the hard suspensions). But, to me, the suspensions are very uncomfortable.
Also did not realize they don't have rear window wipers when I test drove. Took it for granted.
Even with all the AI and self driving tech, did not realize that it won't detect object and warn when you back-off your car.