I have used insta bust and I would definitely recommend the gel but the capsules didn't do anything.
Now here's how th gel works it is what's known as a vasodilation topical.
Vasodilation is a fancy term for causing veins and capillaries to dilate or get bigger. The increased blood flow to the area causes swelling and they get heavier, and jiggle more! Speaking purely scientifically of course
The gel works pretty well though I have noticed that I have to use more than what they say to. They say 3 squirts on each breast and massage it in. I generally have to do 3 squirts and massage than wait about 10 minutes and apply again but once they start to swell you can feel it. Actual swelling may vary depending on how dense your breast is as far as capillaries and veins go. In other words the more you have the more you get. I generally don't get a lot of swelling yet because I just started NBE so I don't have all the insides yet, but am still loving what this stuff does.
I don't use it as much anymore because it is kinda expensive for no more than you get.
Hope this helps and Good Luck! (Don't forget to have fun!)