As a follow-up, I don't see any way insertion of the Kindle cover hooks could cause a cracked case unless someone had no idea how they worked and forced insertion or removal. The pictoral insert with the cover is not the best, and we all know how many people (my wife for example) never RTFM and then wonder why they can't figure things out.
I don't have a solution to the spontaneous reboot problem because I don't have it and haven't tried to analyze it. My only problem was a total freeze in sleep mode which I've overcome with my own solution mentioned elsewhere. It works for me. I like the official Kindle cover for it's protection and appearance. I'm delighted with my two K3 WiFi's and unlighted covers. I hope those who have other problems get them sorted out because it's a great product at a great price in today's market.