Not sure what the status of CSFB/eCSFB here in the rollout. But my wife got an iPhone 6 on Sunday, and is updated to 8.0.2. But when the Phone is on LTE, she often cannot receive calls. I can see it sometimes gets kicked to 1x (from LTE) when I call her, sometimes it rings, but sometimes it still miss the call (not ringing) even on 1x.
Since receiving call is very important on a PHONE, I turned off LTE for now. Also, 8.0.2 doesn't seem to have the Personal Hotspot option in Cellular Data menu in the Settings app anymore?