Two problems related to carrier/rack have been reported for the 2011 Toyota Prius. The most recently reported issues are listed below.
I was driving on a highway in the country, go about the speed limit of 55 when I heard a very loud sound like an explosion or gunshot. I had the cover to the sunroof open and when I looked up I could see that the sunroof was shattered, crackled everywhere, but intact. When I pulled over to look at it from the outside, I could not see any debris from anything that would have hit it. . Instead it appears to bow from underneath and the sides have linear cracks all around. I was not close to another vehicle when it happened either, so I do not see that it could have been caused from anything externally. This could have caused me to be distracted to cause an accident or injury if the glass had entirely fallen through to the inside.
I was driving on interstate 20 with my wife when the sunroof exploded. There are two panes of glass and the exterior pane sent shards of glass out onto the highway. The internal pane of glass stayed in place but some shards of glass fell on my wife and myself. The Toyota dealer says this was due to a crack from debris which hit the car and compromised the integrity of the sunroof. They could not prove or show any mark indicating this as a fact. It was a very scary situation and I feel our sunroof was materially flawed and Toyota should be responsible for the problem.