Of course the big screen kills the battery...
That being said, I think plenty of people have bum batteries. On Friday, I spent all day listening to music, and probably 2-3 hours playing actively with the phone, and I made it from 630AM to about 9PM before I got a low-battery warning. Yesterday, I went from 800AM to Midnight, and when I put the phone back on the charger, I still had 50% battery. Also, I dont use 4G at all.
40% battery in 3 hours isnt normal, unless you're on 4G, and actively using the phone.