none so far that I've had or heard about... had 1 friend, just yesterday say that his original Day One Xbox One is dying, but that's it.
extended warranties are a scam... imo.
I personally skipped the S's, because I have 2 Xbox Ones, waiting for the Scorpio next year.
Depends on who it's with.
IMHO the MS Warranty on my Xbox 360 and Xbox One has saved me at least 1200, as my Xbox 360 was replaced at least 5 times since Launch, the one time I did pay the $130 for repair, MS Send me a Check a few weeks later, as it was covered under my warranty on file.
My Xbox One had some Issues after the first year with SATA Chip, and HDD Problems, Ext. Warranty covered it, they replaced the mainboard etc.
I wish i had gotten the warranty on the controllers too, as one of them had the dreaded "Power On/Off" Problem caused by a Burnt out Capacitor behind the D Pad. So It no longer stays on or connects to console, turns on and then turns off, if I plug it in, the DPad gets Very Hot.
Though I found a nice DIY Repair Video, I might try it,
But I Have 4 Play Charge Kits and only one controller at the moment...