I have the OR Ninjaclava and love it. I bought it off someone at BPL who didn't care for it so much, so it's obviously a preference thing.
For me, it does a great job regulating temperature, fits comfortably, and covers nearly all of my face when I need it to. It's easily convertible into a warm beanie, so I don't need to bring anything else for headwear unless we're talking extremely low temperatures.
I haven't slept in it yet, but will probably be taking an overnight in two weeks, so we'll see at that point. I'm assuming it'll be comfortable.