It's not a huge deal for me because I park our car, at most, three or four times a day, usually in angle spaces or in our garage.
If you park your car dozens of times every day (package delivery person, estimator, appraiser, or sales rep are some occupations that come to mind) in '90-degree' spaces, such as small urban parking lots, high-rise parking garages, some malls, or parallel parking, by all means test-drive a C-MAX and park it several times in each scenario before you decide.
The published turning radius of the 2013 C-MAX is 19.2 feet, so the curb-to-curb turning circle would be about 38.4 feet.
I don't know where Edmunds.com got 35.8 feet reported here - maybe a dyslexic copy-editor?
In comparison, a current Chevy Suburban turning circle is 43 feet.
We own a 1996 Taurus, and its' turning radius is virtually identical to the C-MAX, at ~38 feet, so the C-MAX doesn't bother me at all.
The turning circle of other car I usually drive, a 2003 Pontiac Vibe is about 35.5 feet, about 2 and a half feet tighter.
I can 'feel' the difference between the Vibe and the C-MAX only when I'm trying to get into an especially tight 90-degree parking space in a mall or downtown parking garage. In those situations, with the steering wheel at full lock, I wish the car could turn about 1 foot tighter than it actually does. So I back up a bit and turn in again.