Mine is going back tonight. Although I have experienced 3 lock ups requiring reboots in the last 12 days, I have none of the other problems. My unit is rock solid, and a pure joy to use. I do feel that many of the software issues will be addressed in the coming months, and would be willing to "beta test" this platform, if it weren't for the one major fly in the ointment.
No matter what I try, the volume in my headphones and on my Bluetooth headset is just to low. I have to crank it to 30, and I still can't here the caller when I am driving. When I take it off of bluetooth and hold up the phone the volume is fine. I even tried a Jabra wired headset, no good, even a different brand BT headset (tried both Samsung and Jawbone), the volume is just too low. And listening to tunes? Well 30 is about where I would start for volume, not cap it.
Everything else is great, I'm returning it and maybe trying a 8x if they have one, if not, I will just go back to my old iPhone 4 and wait.