The alloy ladder that comes with the Columbus is tested to over 400 pounds so it should be fine. This ladder has to function under very tight guidelines. First it has to fit in the tent, with your stuff, so it has to be thin and light. The alloy ladder is derived from their steel expedition ladder and they have made it to be able to be repaired, anywhere. It is assembled without one weld, all fasteners but the fasteners may loosen with time and if your ladder is a little wiggly, just tighten them up. The locking mechanism is a little confusing, the old steel ladders didn't have them, they weren't designed for pavement. If you are in dirt or sand or mud you don't need the locks, you step on the bottom rung and the feet of the ladder will sink in and set. The bottom half is stabilized by the dirt and the top is supported by hooks on the tent. In pavement, your ladder will slide into the vehicle if you don't set the locks. We use to get around this problem with the old steel ladders by bringing a rubber mat if we knew we were going to camp on pavement. The mat keeps the base of the ladder from sliding. The old steel ladders were cool because if you needed more traction in sand you could put each half under your tires in a pinch. You would have to unbend them so they would fit together again but they ladders were designed to take a lot of abuse.
however the existing ladder gets a little sketchy sometimes and wants to slide laterally on imperfect ground which is usually the case camping, it is just a bit thin and flexy.
