1000D nylon is a step up from the 600D used on standard gym bags, chosen for fighter bags specifically because the external glove holder and multiple zip points create more stress on the fabric than a simple duffel design.
MMA gyms and fight teams needing one bag to carry gloves, wraps, shin guards and a change of clothes to competition are the main buyers, with the external glove holder being the most-requested feature over a standard gym bag.
Check zipper teeth for trapped grit after gym or outdoor use — 1000D nylon holds up well, but zippers are the first component to fail if sand or chalk dust isn't cleared out periodically.