One of the few gripes I have with the Mustang is the headrests that came with the car. They are canted forward at such an angle that I found them to be uncomfortable.
The problem is the Federal safety regulations that decreed the headrests (actually they are head restraints, not head rests) should be no farther than 1" from the back of the seat occupant's head. I don't know who's head the Ford engineer designed these for, but the only way I could halfway comfortably sit in the seat was to pull them up to the top of their travel and lay the seat back, but that was not a comfortable angle for me to drive.
I ended up taking them to a local machine shop, they were able to bend the bars on them so they stood upright a little more. This was better, but still not optimal as I still had to lay the seat back farther than I liked to be able to comfortably drive the car.
A quick check of the Mustang message boards reveals that I am not the only one. Older model cars (2005-2009) with similar seats have aftermarket headrests available that are adjustable in tilt, but the 2010/2011 do not.
Mustang Racing Technologies has released a version of their tilting headrests for the 2010/2011 Mustang, and they have them with black stitching to match the GT/CS. I ordered a set and they came in a couple of weeks ago.
My first impressions weren't very favorable, the MRT headrests are physically larger than the stock ones and look kind of bulky. Also the grain of the vinyl is finer on the MRT units when compared to stock. Overall they are well made, but the differences in size and style kind of threw me off for a bit.
Then I put them in and tried them out. The difference in the comfort level is like night and day, even though I had taken my old headrests to a machine shop to have them bent they still don't stand as upright as the aftermarket units. The MRT headrests have a four-position adjustable tilt, so no matter how bulbous or flat the back of your head is there is an angle that will fit you comfortably.
I've had them in for a couple of weeks now and I can't imagine ever having a situation where I would want to put the stock units back in.