How good is the Galaxy S III's battery life?

Long story short, I bought the HTC EVO 4G LTE (The US carrier, Sprint's variant on the HTC One X). Sprint has a 14 day return policy. For me, it ends on Saturday. I'm considering the GSIII.

How's the battery life? How well does it do when you're using 3G?

But most importantly, how badly does heavy texting (as in, new text messages every minute for about 4 hours straight) effect the battery?