I have not tried the rebuilder, but I've been using the Micro Tek on my daughter's paint. He has a horrible tail itch and we've been trying to figure out what is causing it. In the mean time, we've been using Micro Tek and it helps stop the itch and his hair starts to grow back. If we stop, he starts itching again.
It is expensive, but you can buy a smaller bottle at some feed stores, and the large bottle last for quite a while. Right now I'm sharing it with the barn owner, we're using it daily on 2 horses and it's been over a month for a bottle and it's half gone. It can also be used on hot spots for dogs and other skin issues in them. My husband jokes that I should use it on my excema since it seems to work fine for the horse's itch. How sweet, huh? I haven't gotten brave enough to try it, but the literature I got when I got samples at a tack sale said that all the stuff can be used on humans safely.