At first I thought it was a topic about lyposuction, however, after seeing the video, and looking at the exercises surrounding the topic, situps, crunches, hanging or inclined situps with resistance, I can see why you'd want to build your abs.
Honestly? I would think that the vacuum exercise is much like any isometric exercise. Isometric (the body working against it's own opposing muscle groups for resistance) exercise works best when done with good diet and fitness routines that include cardio/strength training based on your goals.
What I've read on the topic is that you can have great abdominal muscles, but if you don't burn more calories than you take in and have a surplus of body-fat collected around your midsection, it's not going to show.
Many myths are about how you can burn fat by exercising the areas that the body-fat has collected in, but this is an old myth, because the abdominal area is the first place body-fat starts to collect and the last place it leaves.
Cheers and peace!