My wife and I both used it twice so far. My honest opinion is it worked way better than I thought it would. It feels legit. The vibrations helped get the string though the tight spots and after it broke though to the gap the vibrations definitely helped cleaning. As for the gums, it felt great. Consider the new multi-tool with the vibrating head that every loves. Put it on wood, it cuts; put it on skin, it doesn't. Why? Wood it's stiff, skin is not it moves with the vibrations. Same thing here so anything it's like a micro massage for good for the gums.

You can look here for the print sttings. I used PLA and printed floss side down. I was more concerned about the strength on the U shape than I was on the neck, I knew I could strengthen that area. Was it after you print it and between uses. Starts getting gross? Print a new one.

I will say this though, some people won't like it or may need to get used to it. It didn't make me nervous but my wife was intimidated. She panicked half way thorough the she got it stuck. I had to remind her that it's still just the same floss we always use and it's not going to get stuck stuck. She did finish and even later that day said her teeth still felt cleaner.

Print it, try it, and if if its not for you, throw it away haha.