I just fitted a set of stretch cv boots to a pair of push in sierra shafts. They went on really easy , to my suprise having read
some bad stories. Saves cutting the joint covers and time. The link below is the set i used.
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top tip cut to size after fitting as I found out to my detriment the smaller they are the harder they are to stretch. Didnt make the same mistake the second time
Never had an issue with stretch boots, ever. Always out-lasted the split boots by about 3x.