I bought these a couple of years ago, when I was having pelvic floor problems. I didn't notice that they "worked" my pelvic floor muscles at all. They stayed in easily, and I didn't need to tense up at all to keep them in. They are, however, fun to wear! The vibrating sensation from the weights inside the balls, is not particularly noticeable, and sometimes I think that I can hear them a little bit, but that may be my imagination. Even without significant vibration, it is definitely arousing to go about my business and know they're there. (It's nice pre-foreplay!) The only drawback to wearing them throughout the day, is that I need to take them out to be able to pee (no fun in a public bathroom). If I'm not in the mood for a large toy, I like to masturbate with one ball inside, as I like the pressure it puts on my vulva/vaginal opening.

They're an odorless matte silicone (so no silicone lubes!) that, unlike my other Fun Factory toys, doesn't seem to pick up every bit of hair and lint. The connector between the balls is very flexible, and the retrieval band is sturdy. The colors are fun, with ten different variations.

Since I bought these, I have had reconstructive transvaginal surgery that made my vagina shorter and tighter, so these are now too long for me. I can push both balls in, but it's very uncomfortable, and it's hard to keep them both in because of the length. The girth is fine. I didn't have problems with that pre-surgery (I used to be a size queen, and these didn't feel particularly large), so this is probably ONLY a problem if you've had pelvic floor surgery with mesh. I'll definitely end up buying the "uno" version.