My vote is for ThermiTight - nothing on the market will tighten skin like that; and it will also "melt" some fat. It is more expensive, because it is "surgical," meaning that the area(s) to be treated will have to be numbed and a small poke is made in the skin in order to get the ThermiTight cannula under the skin where it will work its magic. Also, because it is surgical, it requires some healing time afterwards - 3 or more months before the area feels "normal" again, but it will look better by 2 weeks out from surgery. The other two devices work "OK," but not nearly as well as ThermiTight nor ThermiSmooth either, for that matter.
Tightening Upper Arm Skin
An in-person consultation would be needed to determine if you are a candidate for any of the mentioned treatments and which would be best for you. In general, ThermiTight is the best non-surgical skin tightening treatment on the market. Please find an experienced provider.