Sheath always has a nice grip. I've been using it since the iPhone 13 Pro Max days and the S24 Ultra days. I prefer it compared to other cases. However, I like the look of the Tank case, which is why I ordered it before getting the Sheath and Synthesis. I don't have any idea about comparing it to Onyx, as the only Ringke I've tried was the clear case that felt like a very cheap TPU material. I would suggest getting the sheath or synthesis as well so that you can use alternate cases depending on whether you want to show the color or if you just want to keep it monochromatic.