I don't lay stripes all that much (probably once a month or so), and I just got 60k out of a set of 285/75R16 BFGoodrich All Terrain's. I can't really complain about that!
But I rotate them every 5-10k miles, which really helps. Most tires places will rotate them for free (if you bought them there), so it is just a matter of finding the time to get it done.