Had a custom cages weld in as you've shown in my 309 stage rally car and it allowed my nav and I to climb out through windscreen aperture dazed but unmarked after rolling 100mph up at Otterburn, shell was mullered but no deformation to cage or any cracking of paint etc at welds.

Also had a bolt in 6 pointer in an XR2 hillclimb and hit a tractor doing 75mph and had a fair old spell in hospital, because it wasn't triangulated the front of the car came back as far as the front legs, which was unfortunatly behind my feet/lower ankle area

Hence I like strong weld in cages now