Will this procedure really help me scale down my thighs?

Using a laser liposuction device is a great option if you have moderate to good skin tone and want to reduce volume in certain areas.  I would stress that your weight should be relatively stable and that you maintain your balance of diet and exercise to maintain that.  To better answer whether Slim Lipo or Smart Lipo is an option for you, it would be helpful to have a picture to see.  Both procedures have a very high satisfaction rate.  Good luck.

Smarlipo and Lipo work by removing fat cells.  There is some tightening of the skin due to fibrosis of the underlying tissue and contraction of the collagen.  Smartlipo is great for targeted areas such as the thighs, hips, abdomen, chest (for men), arms, chin, etc.  

Any kind of liposuction removes fat to make an area thinner.
But it will not make you less "jiggly." In fact, with less "stuffing" in the skin, the perception of looseness sometimes increases.
Patients need to understand this. It makes people thinner, but not younger.
The claim that certain methods of liposuction tightens skin is as old as the procedure itself. And like miracle fountain of youth drugs, NOT ONE has ever been shown to achieve this. Ultrasonic liposuction and superficial liposuction have long been claimed to increase skin tightening. But this has never been proved. And at best, they might only make up for some of the increased laxity that results from the removal of fat of the procedure, but they would never increase the tightness relative to where someone started out before surgery.
SmartLipo is the latest fad liposuction procedure, claiming the ability to tighten - but without any proof. The buzz at the recent American Society for Aesthetic Plastic Surgery meeting was that SmartLipo was a gimmick, and the procedure is held in disrepute as a marketing device by many respected plastic surgeons.
So, if you want to be thinner, get lipo. But don't expect the jiggle to get better; you should even be prepared for it being worse.