I still suffer from the same problem, and the thing is that my phone was very good before and never rebooted, but suddenly it resets A LOT...
I tried hard reset, and nothing happen. So I tried WDRT and remained on the release build and still the problem still exists!!!!!
I really don't know what to do, and is it a software or hardware problem??
Unfortunately I'm not from USA so it's not as easy as getting a new one here
I'd bet this is due to recent changes, almost exclusively. My phone had one hang (all Release Preview builds) up until 494, when it's hung a couple of times.
Then, after the firmware update, I managed to hang it again, testing the "shouldn't double-tap wake in your pocket mode", where it was trying to "look for me", but hung and eventually crashed, probably not super-well tested, yet.
I'm leaving feedback for this last one, as it's pretty quantifiable, although I haven't managed to repro again, yet.
Please, take the time to leave feedback, if you're hitting these (if you have your phone set to send all crash data, then MS will also have corresponding dump files that are close to your feedback time), so they get looked at, if they're frequent and repro-able.
Sometimes they don't have tests for real-world stuff, it's not as easy as you'd think, so we have to do our part...