Plagiocephaly Helmet- Your Story

My daughter has Torticollis and recently we've noticed one side of head is beginning to bulge out while the other side appears to be caving in. We're getting the eval done on the 1st to see if a helmet will be required to correct this. (Chances are, yes.)
How severe was the difference in your child's head sizes, if s/he wear/ wore a helmet? We're seeing more than 1 inch in difference right now between the higher and lower parts of her head.
What was the casting/ fitting like? How do they cast over hair if the baby has very long hair?
What have your experiences been like, in general? How many hours a day does your child wear the helmet. Did you have trouble getting insurance to cover it- did you have Medicaid or Medicaid as a supplemental insurance? How much it did really help or not help? Do you feel it helped or hindered other milestones- such as sitting unassisted.
You don't have to answer all those questions- just some suggestions!
Thanks for sharing your story!