I haven't tried it personally. Though I ordered the Transfem/Bountiful Breast pills about a year and a half ago and that experience was a sheer nightmare...
I'm usually pretty cautious about online transactions, but at the time I was utterly miserable with my masculine appearance and the realization that I'd put feminization on hold for so many years (early 30's now) and wasn't getting any younger left me feeling desperate. So, I prepared a list of questions and tried to contact the company, Avalon, with no response. I foolishly decided to order anyway.
The next day I figured it wouldn't hurt to check a few forums to see if the product actually worked. To be honest, I found mixed results, but nothing positive. I found testimonials that seemed oddly similar to the advertisements on Avalon's site with pictures that illustrated either dubious breast growth, or growth that was obviously a result of a gain in overall body fat. Additionally, I found a few threads in which several users adamantly proclaimed that the product had no effect whatsoever.
Panicking that I just threw away $600, I emailed my list of questions to Avalon and called them while I waited for a response. In both instances, I was able to get in touch with them immediately, but in both responses, buried underneath the sales pitches was a clarification that contradicted the website's claims: The results were NOT permanent, neither for feminization nor for just breast growth. So naturally I decided to return the product once it arrived (as it was too late to cancel the order).
This proved to be more challenging than I could have possibly imagined (depression about the whole fiasko not helping). I sent an email asking for a refund. A few days later later they said 'sure', just as long as the bottles were unopened when I returned them, which they were. So I sent them back.
That was the easy part. Over the next couple months I patiently waited, but heard nothing. Finally I went and tried to call them but encountered a nice variety of reasons that my issue should be avoided, the most common of which being that the recipients were only a call center and could only contact Avalon by leaving messages. Eventually I got excuses such as the lady handling returns was on maternal leave (really, the entire department then?) and her replacement had no contact information. I also encountered other classic ones as well, including indefinite holds, call transfers that disconnect, and given alternate numbers that don't exist. So I tried emailing them--unsuccessfully with every email address on the site. They kept getting bounced back due to some technical error. I tried the forum on the site only to find that didn't actually exist. I tried the Live Chat feature only to find that that didn't function.
Every few weeks I tried again, increasingly aware that I'd been scammed yet still wanting to give them the benefit of the doubt. Finally after 6 months I decided to give up and reported them to the Better Business Bureau for Utah. I thought that would do something but apparantly no one ever visits that site to read about good/bad reports, so that was a waste of time, lol. Lastly I went to my credit card company only to find that I was just outside the 6 month window of fraud protection.
Moral of the story:
Maybe Transfemme works, maybe not. But if it did, wouldn't they be more honest about how they do business?