First off, The few times I've had to use Factory Warranty service it all went perfectly. One was a DOA s7, promptly replaced with a new one (yes I checked it out) after they got the dead one in China. 3 other times were dead boards, all promptly replaced.
It makes me wonder if the quality of service and product depends on the size of your purchase. Bitmain would no doubt be reluctant to send larger customers crappy products and they definitely wouldn't treat them like crap as well.
To your others points, yeah those are definitely issues that Bitmain should have sorted out long ago if they had any type of professionalism.