My brother's first dually was a Yakuza Kumicho. He cracked the swing-arm in (i think) 2 places. Then he got it sent off to Gripsport who fixed it and reinforced with new welds and steel plates in the middle of the triangle.
A while later he cracked it in four places.
I dug up an old pic of the first time it cracked, before it was gusseted.
Still, both times it cracked was casing a road gap, first time snapped 3 spokes at the same time as the swingarm.