Works for me too, Julie.
I think 2 factors have to be worked in.
Time; I have been on herbs for 3 years [not yet 32 months, on PM] Give it time. Most genetic females take, from around 14 to 18, to fully develope. Why should we expect more.
Genetic disposition; some women, of similar frame, have big boobs, some small; just the way of the world!
If you saw Jenny-Anne on Embarrasing Bodies; you will take my point. I have boobs, the size of hers, without surgical enhancement and she has been on prescribed hormones, longer, than I have been on PM. I am blessed with a body, that is receptive, to growing boobs. As Beverly has indicated, PM .co .uk has worked for me; they are cheap, efficient and supply a product, that works. By all means try BO, but I cannot see any reason, to try a different PM brand.