Posting a screenshot from my ATT s4. I used to get terrible battery life with the stock ROM, no matter what I tried to help it. Now with CM 10.2 2013-12-05 I think I have a very good option. The only issue I had to resolve was messaging app. I wanted to use the ATT app, and found out I had to remove or disable all competing apps, like chats, hangouts, and 3rd party message apps. Then it would set up fine as long as you have 3 bars signal.
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