[quote name='tauzero' timestamp='1409057325' post='2535855']
I've got Schaller or Schaller clones on all my basses and guitars. Never had a problem. They're all positioned so that the strap buttons sit in the cups, so the retaining button has no stress on it, it just keeps the button in the load-bearing cup. The only thing I have to do every now and again is a little nut tightening, though most of the clone straplocks have two nuts on each straplock, so the second one locks the first one.
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Ditto.
25 years using them and the original strap fittings that I have on my strap at present have been transferred between two straps in that time (first one the leather wore through) and no failure as yet. As has been highlighted, I have the button on the bass resting in the cup... can't imagine why you'd do it any other way mind!