I have been having issues with 6.1.3 and battery life-getting about 6-8 hours of stand by with 1.5-2 hours of usage. Prior I was getting in excess of 18+ in standby with 4-5 of usage. They offered a replacement phone, but not really sure that it will do anything. Worth taking it or not? I have done a DFU restore and multipe restores without using backup.