I dont know, my S3 gets good batter life. Granted I am running a ROm and a different kernel but, yesterday, I was Bluetooth from 9am to 11pm at work.. listening to Google Music (I bought the $8/mo thing they have) and talking on the phone. Talk time was right around 5 hours. Music was about 4 hours. Played about 10 games of spades, sent about 50 emails. Battery was still at 46% when I walked in my front door.
I bought the S3 after the S4 came out.. im old so, latest and greatest aint shit anymore. Saving money is..lol
Got my wife one too. She had an iphone for a few years. She was hesitant but after about a week of using it and me taking the time to calmly help her along the new ecosystem that is Android, she loves it. Hell shes found shit I didn't even know about..lol