The JD design is far superior to the skidsteer quick attach for low lift capacity loaders. It keeps the bucket in close to the lift pins, saving the limited lift capacity. However it has some design limitations as well. When back dragging the weight is on two small pins that have holes drilled in them. The limited capacity and low traction force of the tractor generally prevent damage, however a stronger tractor could cause the mounting pin to break. Also wear in the mounting pin can degrade its strength and can break if enough use is put on it. Replacement is cutting and welding a new one on.
The skidsteer quick attach is a much more durable bucket attachment system. However it sacrifices some lift capacity due to the minimum depth of the latches. On a small sub compact this reduction can be noticeable. The locking pins can break but it is easily replaced with basic hand tools.
Both have their place. But on mid sized compacts and larger I prefer the skidsteer quick attach.