I've used Dragon Sheilds, KMC, and Player's Choice (although PC I haven't used recently) and KMCs are the play. My fiance and I had both had KMCs and they've lasted longer than any Dragon Shields that anyone we know that plays the same amount as us owns. Dragon Shield certainly aren't bad, but I'd take PC or KMC over DS anyday.
Word. I think that KMC, PC, and DS are basically all tier 1 and everything else is below that, so it doesn't really matter as long as you're using one of those. My KMCs have lasted longer though, as I've said, but idk. I've heard PC has gotten better than KMC though, but have yet to try 'em out.