I am towing a Fiesta with a 2011 Sunseeker 2300 – so far, 1,435 miles without any problems. Because my Fiesta was built prior to 7/15/2011, I had my local Ford dealer perform the recommended transmission code update. The readout now clearly indicates when the vehicle's transmission is properly set up for towing. The Fiesta has proven to be (in my experience) a very user friendly and reliable dinghy.
For more on this topic, Google “Ford Fiesta dinghy towing.” I think it is reasonable to assume that at least some of the earlier horror stories resulted from the transmission not being properly set in the neutral mode.