I had a weird issue with 8.3 that caused me to go back to 8.2 yesterday. I was on the public beta with a Gold iPhone 5s 32GB AT&T...It died before I left for work because I didn't put it on the charger before I fell asleep. So I put it on the charger in my car and it refused to charge (just kept showing the battery icon). So then I held the power button and home button for 15 seconds and it would act like it was going to boot, but it would just go back to shutting off before it finished. I thought maybe the car charger was bad so I plugged it into the wall outlet at work once I got there...same thing, no charging and no turning back on.
I put it in DFU and went to 8.2 and it has been fine since. I am not knocking 8.3 though...the battery seemed to last quite a bit longer and it was pretty stable. I think I just had a freak issue.