No one that affect the quality of life, Spider do as well if sometimes not better than other mutations, I have always found them more inquisitive.
As a breeder you have to make your own choices and draw your own lines, mine are at the possibility of severe deformation which is why I don't work with Super Black Pastel but work with other Black Pastel Combos.
Ultimately even when working with other animals things happen, kink, underbite etc and that when the breeder has to know what he has to do regardless of the paint job, I have euthanized animals in the past that wouldn't have survived or have a quality of life and known were Spiders.
Remember every mutation is a defect and there are purist out there (old school ones)