First, I believe the 0.4% number came from Sony so it's hard to say whether that is accurate or not. Second, I really don't think we'll know until more units are out there and they've been used for a longer period of time whether there are any sever problems. From what I remember, the Xbox 360 issues weren't seen as severe during the first week. It took time for people to really get a good sense of how large the issue really was.
As for people reporting issues at launch; that will always happen. Hardware has a failure rate and the PS4 is not an exception. Even after launch window hardware will have failure rate. I bought a 360 two years after launch and same with PS3. Both failed and I had to replace them.