Marie, seems to be pretty much a guarantee with the Brava vacum bra, too, and less chance of surgical complications. Cheaper, too!
I repeat, I did a second major in human biology, (First was electronics, somebody's got to design medical equipment, right?) and from all I know of biology, the vacuum bra makes sense. You put tissues under tension, they grow. It works for muscle, bone, skin, and they've now proven it works for breast tissue. Heck, penis pumps would probably work, too, if men were willing to wear them ten hours a day, week in and week out. (Ick!)
Now, the upside is lack of surgical complications, (Which range from loss of sensitivity, to death, though the latter isn't all that likely.) and a completely natural result, because the result is just bigger breasts, period. It's all you.
The downside is that it takes time. Lots of time. Ten hours a day, 7 days a week, for three months, to roughly double breast size. Roughly a year to exotic dancer size. NOT, slap down a few thousand bucks and walk out looking like Ms. Charms.
But, speaking not as a doctor, but, yes, as somebody with a substantial knowlege of human physiology, I'd say it's the way to go, if you've got any patience at all. Going under the knife is something smart people avoid.