Maximum width of comments on wide screens

When posting a comment, the width of the text seems limited. When I removed the max-width from the p and li element, it filled the box as I expected it to. (Source)

To me, the second one looks better. Some padding left and right could be added, but I certainly wouldn't use a fixed maximum width there (A percentage would be fine, I guess).

Edit The seems seems to apply for posts as well.