YES, this works. It's not subtle either—this device works VERY VERY well, and the results for me are instantaneous. I never imagined any treatment—much less a DIY home device from Amazon—could be so effective. It's truly a game changer.I bought it to get rid of pesky underchin chub. I use it on the highest setting for 10 minutes on each side of my jawline / neck fat. Sometimes I add an extra 10 minutes. The first week I used it every 2 days, then after that I've done maintenance using it once or twice a week. I have only had this for a month, and the results really are dramatic and long-lasting. My jawline really does look sharper and tighter and I feel like there is visibly less fat under my chin.I have also used it at the hairline above my temples (medium setting, 5 minutes each side) for a subtle eyelift effect. It is terrifyingly effective, to the point that I am hesitant to use it on any part of the rest of my face in case I accidentally make any changes I regret.I've read that the initial dramatic tightening effects from RF are temporary. But I've also read that the home devices actually are capable of causing permanent fat loss. In my experience, I noticed the effects wearing off about 4 days after the my second treatment, but nowadays it seems like the results are more persistent.In any case, for good or bad I would not dismiss the fact that this powerful device could cause permanent fat loss, and therefore you should be incredibly careful using it on your face in case you cause permanent changes to your facial fat pads.Lastly, I want to give a shout-out to Mlay's amazing customer service, which is honestly some of the best customer service I've experienced on Amazon. I initially left a negative review because when I first ordered, the Amazon warehouse sent me a used unit that had not been inspected and cleaned. Over the past month Mlay customer service has reached out to me several times to follow up with my experience. They offered to send me a new machine. After I told them I'd already made an exchange through Amazon and was quite happy with my new device, they nevertheless offered to send me another tube of their gel to make up for the trouble, even though it was the Amazon warehouse's mistake.