Has anyone here used the Olympus 9-18 M4/3 lens?

I'm trying to decide whether I should get a NEX-6 with the 10-18 or an OM-D with the 9-18. Please, let's not discuss the bodies right now, I'm only interested in the lenses. (I know there's also the Pan 7-14, but I'm not interested in that lens as it's too big and doesn't take filters).

So...if you've used this lens...what's been your opinion of it? Can you compare it to a Sigma 10-20, Canon 10-22, Tokina 11-16 or even a Canon 17-40? How does it stack up against those lenses?

Thanks!