The focal length of 9-18mm allows the lens as "always on it" to use glass. The results are impressive. The lens has a nice sharpness and is relatively light-strong for its size. It is very quiet and can therefore also be well used for filming.
The lens is very small, very light, has a metal bayonet, acts and is of high quality. It's great fun to photograph it. The possibilities of this glass are really very, very diverse.
I agree with the Vorrezensenten jazzy at: predicate: Highly recommended!