it is not a matter of size or pretty, but you have to consider the possibility of raining or snowing. The lugguage bags are not fully covered when being transferred from / to the airport and the plane. If it is raining / snowing, the soft case may get wet and so as the clothes inside. There was a case when I first traveled to Hawaii years ago, there was a couple in our tour with all their clothes in their soft case got wet on the first day of arrival since it was raining heavily.