I would advise against update.
I updated my phone to 5.0 from sammobile british version and battery life is terrible.
Actually the problem I am having is battery life during calls. Before update i could have a 2 hour conversation with gps on and recording my 2 hour walk and the battery would go down 5-10%. Now I have a 1/2 hour talk with nothing else on and the battery drops 15%.
Battery life when idle is better than before, so i suspect there are no background apps that drain excessively. Is it possible that it uses 3g/lte networks for calls now? I can't find those options.
I'll post this as seperate thread also.