Sleeved all my cards today, and I have to agree with some of the more sensible complaints online about the variability in the cut and finish of the cards, for a game where you're meant to be hiding the cards you have in your hand. There was a definite, though small, difference in the size between the original cards and the Orruks/Guard, and the Orruks/Guard cards seemed to have a smoother finish to them - they almost feel a bit more glossy (if you catch my drift).
Now they're sleeved it's not going to make a difference, and I doubt I'd be bothered to learn the difference enough even if I play someone with unsleeved cards, but I hope GW tighten it up a bit going forward.
Still loving it though, even if our game last night was a slow burner.