Buy them if you know what we do

In terms of price / quality ratio is very good. At this price there is no auto focus, everything is manual but there is a trick: open to 1: 8 and remote debugging to 1 m, and then everything is clear. There is also a slight distortion that appears at the center of the image is visible if one takes a picture of a horizontal element, and it's not easy to fix it completely as it is a remote area of the image.

Then after, photographs ultra wide angle (mounted on a Full Frame it feels true 14 mm, and it's really quite surprising the first time) it's nice, but it is special and I think it's still hard take pictures in ultra wide angle. I bought the objective there is more than one year to try. I sold now, because it's not my thing. Contrary to what I thought, this is not practical for landscapes (in my opinion) because the angle is so great that the ground before the landscape occupies a large part of the photo. This lens works well for pictures in narrow alleys or by being extremely close to a building that can not move away, by cons for the rest I do not see any added value.

Think also to the absence of AF: yes to 1: 8 with 1 m distance everything is clear but if you wanted the opening to 1: 2.8 the focus is manual, and it is difficult to succeed shot "on the fly".

In the end it was more a toy than anything else funny in the beginning and then you realize you can not make beautiful pictures UGA everywhere. I had avoided taking a fisheye exactly why (the aspect we quickly abandoned toy) and in the end I found myself in the same situation.

If you want to try the photo UGA I think it is a very good goal to start, but know what to expect afterwards. Like many things it's still a matter of taste.