It's actually not that bad. I'm not what you would call "impressed" by it, but it's not nearly as bad some of the things I've heard about it. There's only a slight degree of warping that five minutes with a heat gun would fix. And amazingly enough, the proportions look almost right for my 5' 10" frame.
And while it's neat to claim that I finally own a Fett helmet, I'm pretty sure I'm going to put it up for auction soon. I'd like to hold out for a fiberglass helmet (wink wink, oh white Mandalore )
So the overall impression is good, and with some work it could be a good helmet.