Double wheels, often found on high-quality "8-wheel spinner" luggage, are generally considered superior to single wheels for several reasons. The two-part wheel system provides significantly more stability and durability because the weight of the bag is distributed over a larger surface area, reducing the stress on each individual component. This design is particularly beneficial when navigating uneven surfaces like cobblestones, thick carpets, or sidewalk cracks, as the double wheels are less likely to get stuck or "wobble" than their single-wheeled counterparts. Additionally, double wheels offer smoother 360-degree maneuverability, allowing you to glide the suitcase alongside you with minimal effort in crowded airports. While they do add a small amount of weight and can technically be more prone to collecting debris between the wheels, the trade-off in longevity and "roll-ability" makes them a preferred choice for frequent travelers. When selecting luggage, look for double wheels with reinforced housings and high-quality bearings to ensure the most reliable performance over years of rigorous travel.