Even smaller & lighter than the 35mm f/1.4 lens, the 18mm f/2 seems quicker to focus - but of course is a much wider angle of view (equivalent to approx. 28mm on a full-frame 35mm camera), which means less apparent depth of field than you might think you'd get from an f/2 lens.
Still, it's a great little lens in use, and delivers the goods as far as image quality goes - and even when pushed pretty hard, doesn't flare too badly - as you'll see from a couple of images where I tried to make it fail!
One thing to be aware of that I've found - with the 18mm, the X-Pro 1 uses the full 0.37x field of view in its hybrid optical viewfinder. In practise, what this means is some pincushion distortion in the actual viewfinder, which of course isn't actually visible in the image itself, it's just the viewfinder magnification you're seeing. So you'll think your verticals are bowing inward towards the top & bottom of the frame, when in fact they're fine - but it does make it slightly trickier to get your horizons level when you're trying to line up gridlines with verticals in your field of view.
Fortunately, Fuji have provided a built-in horizon line you can enable in the OVF, so if you're having recurring problems with it, just turn that on...problem solved.
Images follow - again, these are tweaked .jpgs from the camera, using Alien Skin Exposure 4 just to make me happy. Enjoy!