Ari Herstand seems to be the leading expert (or perhaps the only one I have seen who is willing to share his knowledge) on this subject, he has tried most if not all of the distribution companies. If you haven’t read it yet, he has an online post about the subject here:
https://aristake.com/post/cd-baby-tu...es-zimbalam-or
He also has a book for sale on amazon, and a lot of other interesting information on his site.