Don't warranty repairs have a free loaner anyways? You can't use the free rentals for regular maintenance visits can you?
When I brought in my car for the warranty repair on my exterior trim and window, they covered the Enterprise rental (4 days). I remember the saleperson also said, any service dept visit that is expected to be longer than 3 hour, they will cover the rental car. Last time I used Enterprise out of pocket, I told them I was getting work done and wanted the insurance rate and it was about $30/day for a small econocar. So, not too worried about getting a car.
I'd rather wait and see how this car does in terms of reliability and like Forddealz said, if better features come out that maybe this car should have come with, I don't have to worry about dealing with an ESP. Being saddled with Sync3 and this underutilized 10" screen would really piss me off, for example--when Sync4 is so much better and actually uses the 10" screen.