Seriously, with KitKat, I can only get about 3.5/15 at best.
But I was looking through some older ROM and kernel threads, and people were getting insane numbers like 6/24.
I decided to revert to a 4.3 ROM, Sense 5.5, but no dice. According to GSam, "Android System" and "Kernel" were still using ~20% of my battery.
My mother's One, I noticed, doesn't have that drain, and uses a sense 5 ROM, so I went back even further.
Now, I can definitely see an increase in battery life, with Android System and Kernel using ~8% of battery. It goes even lower during standby.
I know the International guys don't have this problem, they still get insane numbers on KitKat.
So, does anyone else want to see if their battery life is better on JB?
Or is everyone here OK with about half the battery life they used to get?