I use the one with the rubber wedge, have one with recurve leather cup and one with longbow leather cup. Have not had a problem with these.
Looking at the draw weights on your bows, i'm not surprised in the least.... The heavier draw weight bows have a lot more torsional strength to them because the limb thickness is there. These are much harder to put a twist in than lighter draw weight bows.... The bows that really need special attention while stringing are the lighter draw weight recurves.
On lighter draw weights, there is a lot less beef holding those limbs straight. When applying pressure to the limbs with the stringer you need to watch how those limbs are coming back closely, and even after you have it strung make sure its tracking straight immediately by drawing the bow and watching the limbs... I've seen a string in the groove setting a bit off center effect the tracking before on some recurve limbs. Sometimes just flipping the string 180 degrees will bring it back in line too....
I no longer build my static tip SS recurve limbs under 35@28" for that reason. They just have too much hook to keep comfortably stable at low draw weights without using carbon. Food for thought..... Kirk