Since this product is a tapping screw, it is unsuitable for the hole where nuts and taps are cut, of course. Also, it will be impossible for metal partners.
In my case I used it for joining ABS plates but I think there is sufficient strength.
It seems that the preliminary hole is 3.3 mm (same as the M4 parallel thread). By the way, because the unthreaded end of the tip was 3 mm, I tried to tighten it with a 3 mm pilot hole, and it was threaded halfway through.
From this, I feel it is hard and brittle compared to polyca thread. (It does not mean there is no strength)