Well my impression is that the freeze issue (battery pull) is software related (some software invoke an old out of memory issue (or memory leak))
Which explains also the lag and the phone becomes unresponsive ;)
Try a reboot before the phone has the lag and very slow unresponsive symptoms...
Have to find time to start a process log file
Despited the fact we have here an second O2X running 8+ weeks now and uptime 320 hours without any problems.
The spontaneous or wall charger reboots are most likely hardware just go for a replacement
Up until now had one freeze with the replacement O2X which I probably can pinpoint to other software (have to test more)...
No spontaneous reboots anymore, but there is always a but lol
Have to test more because I'm very cautious with this phone to conclude anything with a almost two weeks replacement old O2X...
I prefer a Gingerbread update without any LG software