Hi all,
I have a '13 500c (US). I haven't found the blind spot to be any worse on this than any of the other cars I have driven.
The trick to eliminating the blind spot on almost any car is to adjust the side mirrors further out so that you cannot see the side of the car and such that cars coming up in the adjacent lane are visible in the mirror until the car is visible out the window beside you. This feels a bit odd until you get used to it, but it does eliminate blind spots and virtually eliminates the need for a head check.
My two cents (and my first post here),
- Kevin