I have one of these now. And it's kind of amazing. Very well made and seems like ideal softness. It's firm enough to insert easily enough and soft enough to smash a little to push the knot in. Especially since the center is hollow. Though the knot is pretty big and i can definitely feel it when it's inserted.
I tried pushing a glass wand inside of it while it was already inserted in me. And that was magic, cause it expanded inside me and I could feel exactly where the end was. When it went through the knot then i could really feel the knot. Gave some similar sensations to an inflatable toy, since it expanded after inside. So could end up having the knot larger than would fit pushing in or pulling out. So felt more like a true tie that way.
Penetrating it felt good too. Different feels with the end plugged shut or left open. Definitely gave some suction feels with the end plugged. I just used a finger to do that and it sealed up nicely for a decent amount of suction. Similarly it would expand and the knot looked especially lovely thrusting into it and having it expand visually. That I'd love to try out with a partner, on either position.
A couple thoughts I had today were if I came in it (or someone else did) I would have thr option to suck it out of the cock end, or lick it out of the vulva side, which is intriguing.
I belive it could be used for a safer sex option too with a condom over the end to prevent fluid contact. It already would prevent genitalia contact as is. I believe the other version has a closed end which would achieve this without a condom.
It does look rather lovely shape. I got thr pink color and it's beautiful. Though a natural color may look more matching to skin tone. Loved looking at it in the mirror with insertedand on all fours. The knot was big enough to stay inside even when I was crawling around for a while and going up and down stairs. The length was comfy for me, though I do take larger things often.
Also there's some affirming gender/queer vibes with this toy. Both seeing it and the feelings wearing it. There probably would be more along these lines being seen with it or using with others. Which I hope to do someday.
All in all really enjoy the toy and I may end up getting the other options too. Highly recommend the maker, great experience and quick discrete shipping.
Thank you to OP for bringing this lovely toy to my attention.