Props to Apple's customer service:
This morning I woke up and loaded a Youtube vid on my iPhone 6. After about 30 seconds of playback my wi-fi strength dropped from full to zero. At first I thought it was my router, but then my iPhone spontaneously rebooted. It then briefly flashed a red screen and rebooted a second time. I was able to get in after the second reboot, but both wi-fi and Bluetooth were disabled and I couldn't turn them back on. Then the phone rebooted again. And again. Twice I tried to do clean reinstalls of IOS using recovery mode, but both times failed due to the phone red screening in the middle of the process.
I made an appointment at the local Apple store over lunch. By the time I got there the phone was now doing nothing but looping in a cycle of booting to the Apple logo, then throwing a red or blue screen, then rebooting again. I told the tech what happened and what I'd tried to do. He did a quick check, said he wasn't going to make me wait, got me a fresh phone, swapped SIMs, and sent me on my way. My last iCloud backup was from yesterday so I didn't lose anything other than a couple of songs tagged in Shazam that I had already playlisted in Youtube.
This was on a 4 day old iPhone 6, 64 gig, Verizon. The store tech said he had not seen an iPhone 6 fail so badly... my luck of the draw. I'm just glad they swapped phones without a hassle or after spending hours on trying to make the dead one work again.