I imagine it is rather vomit inducing the first few times. I also imagine it depends on what you're doing in game, how you're sitting, position and whatnot. For me personally, getting on a bus can give me a banging headache sometimes, especially if I face sideways, other times I can perfectly fine, even reading on my iPod. All depends on the situation.
As for the price
I think I'll pass until it has mass support. I look forward to giving this thing a test though.