Sideloading the OTA is the way to go. Did it on both the 2012 and the 2013. Only problem I had was older drivers that didn't want to work in Recovery.
This! Adb recognize my device but once I'm in the bootloader it does not. I guess windows 8.1 issue as I had the same issue when rooting my HTC. Went through hell for a work around. What did you do to get it to recognize the device in bootloader? Thanks!
Posted via some candy.
You do not have to unlock bootloader to manually install ota file. Now installation of the images Google posted, yes you have to unlock bootloader. I recommend manual install ota zip as you don't have to unlock the bootloader and you won't lose data.
Posted via some candy.