THESE are very pliable, both sets (the ones for sale and the ones I already had)
Often times the cause of a torn boot could be because the pressed-in ring doesn't "spin free" on the ball joint stud. (not saying a boot couldn't be too old and dry either) It is a good measure, before riveting your boots etc. together, to stretch the ring inside of the boot enough (of file the ring, your choice) to snuggly fit around the ball joint shaft, yet spin freely on the shaft also.I would say a thousandth or two of an inch clearance would do. 67289gta (John) had a similar problem occur with new reproductions boots and had to do a repair (file down) AFTER riveting the assembly. It is a much easier task while the boot is off and separated from the ball joint.