I have a 2013 Ford Fusion with Sync and MyFord Touch. I've honestly not found much issue with it, but that doesn't mean I haven't found any issues. I actually like Sync over what GM and Nissan have for UI but the touchscreen is, admittedly, crap.
The only feature I have but can't use is the speak-to-text feature; I assume that's a Windows Phone only feature. I also don't like how the vehicle reports in maintenance checks. Instead of using my phone's internet capability it makes a phonecall instead.
Other then that, I have no problem with it.