Which one can capture the most of the area without getting any significant distortions (fisheye type)?
Try Sigma 12-24 mk2. It's not particularly fast, though. But 12 mm is crazy wide.
If you want speed there's Canon 24/1.4
Which one is the best? There's no answer to that. Canon 16-35/2.8 is a good compromise between wideness, speed, focal length range, and image quality.