Andy_P - I can attest to screens cracking. My Dad purchased the 550XXL in February of this year. He never used it, and cancer took his life in June. While in Arizona to help my elderly Mom get situated, I stumbled on this GPS unit that he bought but never used. Mom said it's mine if I wanted it, so I registered it and got it all updated. I mounted the unit on the dash with the suction cup attached to the sticky round surface. I love the unit and works very well and is really responsive for me. Today I went to lunch and noticed the unit had fallen out of the round mount and laying in my Jeep console (maybe a 2 ft. drop). To my horror, the screen was cracked, however I could turn it on. It was not responsive when touching it to enter a POI, Home or anything else. Great, I get this thing and already ruined. I called TomTom support and the guy seemed like he was willing to help me, but then said sorry too bad and that was it. Since he never asked for my email address or ask me any questions about who I was or the GPS info, I figure it was worth a try to call back later tonight. I got a very nice rep who seemed genuinely sorry about the issue with it falling out of the mount and the screen cracking. She had me scan the receipt of purchase (thankfully Dad kept that), and she made an exception and is now going to send me a replacement (I don't know if it's new or refurbished), but it was very nice because I now get a second chance with this unit.
The reason I am saying all this Andy_P, is because I can verify that it doesn't take much apparently to crack the XXL screen.