Ultra wide angled, Good contrast and image quality, fast focus, quiet
Cons:
Distortion around the edges at 10mm, expensive for an EFS lens
Great lens for landscape photography! Also for creating interesting shots with architecture and lines. Be careful though if you are taking pictures of someone that you put the subject in in the middle of the picture otherwise the distortion will be significant and rather amusing. Cost is relatively expensive for an EFS lens but it is worth it for landscape shots alone.