It really comes down to personal preference. Soft-sided suitcases tend to be great for overpackers, as they offer additional give and the exterior pockets allow you to pack last-minute essentials with ease. However, "a hard-sided suitcase can be better at protecting fragile contents, assuming you cushion it well inside,” says Phillips. “On the other hand, that rigid exterior makes hard-shell bags unable to be compressed to squeeze into tight spaces like soft-sided bags are more apt to allow.”  It’s also important to consider what each format offers interior wise. “Soft-sided luggage usually opens to one main compartment that may have interior pockets and/or suiters," says Phillips. "Hard-sided luggage is typically made with 'split construction,' meaning the bag zips down the middle and opens into two shallower main compartments, like a clamshell.”  If you're basing your decision on durability, you can't go wrong with either. According to Phillips, “Travelpro puts both its hard-sided and soft-sided luggage through the same rigorous testing. [Our] soft-sided bags are made with high-density nylon fabric, and our hard-sided luggage is made with a lightweight polycarbonate shell.”