Hard to give you an honest opinion of a phone that I don't own and have not played with. All the stuff I've read suggests that it's a good phone, and the S4 Active is particularly interesting if you have a tendency to be clumsy near water.
But with the technology moving so fast there are already better phones out there (well, depending on your carrier; and of course, depending on what you're really looking for in a phone). If I were going to buy a new phone I'd be looking at the LG G2 or Sony Xperia Z1, and perhaps the yet-to-be-announced Google Nexus (5?). As with the S4, those are phones that I've read about but don't own, nor have I played with them. And they're selections based on my interests, which may be totally different than your SOs.
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