After leaving my F71 on for an extended period of time the front display eventually freezes while showing some garbage screen. The network interface seems to continue operating fine. The only way to get the front display back is to hard power cycle the unit (unplug the mains power cable).
Just be aware that updating to a new OS and firmware version will result in some changes to functionality. I think all these changes are for the better, but this can still be disruptive if you were used to the instrument operating a certain way. You can read the full changelog to see what has changed over the months, but the breaking changes I can think of that have been made relate to remote communication with the instrument. If you update and something stops working that was fine before, please let us know.