It depends on who you ask. 4-wheel suitcases are particularly popular for their ease of use, especially if you have a lot of walking to do during your travels. They distribute the weight more evenly and reduce the strain on your arms and shoulders compared to traditional 2-wheel suitcases. But 2-wheel suitcases do well on rougher terrain when it's easier to pull your luggage instead of rolling it. Plus, they typically have more packing space and require fewer repairs.