If you already have the original German-made (Sch...) locks installed in guitars and straps you should not get these, since they are not fully compatible: the older, more expensive locks in the straps you already own will lock into these, but they are not as tight as they should and the guitar swings a little bit more than necessary. I would keep to the original locks.
If these are the first straplocks you buy, then there will be no problem. They are not perfect clones of the others, but the quality seems good and they are way cheaper.