The adjustable belt actually stays put instead of sliding around, which was my main worry. The 20 cm size hits the right spot without being too much. Honestly a great pick for couples who want to switch things up.
The adjustable belt actually fit both of us comfortably, which I wasn't expecting since we're different sizes. We tried the role-swap thing on a whim and it turned into a genuinely fun night. The 20 cm size is substantial without being intimidating.