HCC Product : Holinic

HCC Product

It is best to blow dry your hair at 45-47 degrees as mentioned in the video. Can cold air setting be used when it's Summertime?
Is it ok to use a brand of the products but not the same products on the list?
Will a silk pillowcase help with hair breakage?
Would it be better to use something like the Dyson Airwrap on your hair rather than a flat iron? Would it be a lot less damaging or just as bad?
Are allergies to things like pets and dust mites harmful to hair health?