What makes a bike pannier ideal for commuting, and are there any specific features or designs that set the best panniers apart from the rest? For instance, how important is water resistance versus durability, and are there any panniers that successfully balance these two factors? Additionally, what role do attachment systems play in the overall functionality of a pannier, and are there any particular types of attachments that are more reliable or convenient than others? Finally, are there any panniers on the market that stand out for their ability to carry bulky or unusual items, such as laptops or change of clothes?