| | Re: What is the best (( 9300 )) OS version for speed and battery life ??
Battery life depends on how much you use the device and what you use it for. If you surf a lot or make many calls, then the battery doesn't last as long. It is really hard to respond to your question since how you use the device will different from how anyone else uses it.
As for the OS, Read the 9300 section and see what other users have to say about the various versions.
Once you get your BB and get it set up as you want, and if things work as you need, it might not be broken and need to be fixed with an OS update.