I think I must have the worst luck in the world. I run every section of LFR on 3 of my toons every week. I MAYBE win something once a week, but when I do, it's ALWAYS a piece for a slot that I don't even need. I've won 3 pairs of LFR boots on my mage, and a cloak on my lock, when I'm wearing a 496 cloak.
Overall, I find this system incredibly frustrating, and just wanted to vent my frustrations/bad luck.