I have to disagree with the durability of invisible thread, I patched a hole in a scrub top with invisble thread(bottom and top) lined the pattern up perfectly and that scrub top was washed weekly, I now have uniforms but that scrub top still exists with no problems washing drying and ironing using superior thread. I think the thread is a personal choice some like it, some don't. To me its just another thread, I don't love or hate it and I am not opposed to using it if it suits my purpose. I do think the durability is there is you use a good brand of thread.