The Basis clamp is not threaded and does an excellent job of clamping the record solidly to the platter. You can literally lift the platter up by the clamp, it holds that strongly. I believe the theory is that the more tightly the record bonds to the platter, the less unwanted vibrations transmitted from the record to the stylus and the better the sound (in the case of the Basis tables, the platter is designed to be similar to vinyl so that playing a tightly clamped record is like playing a 12-25 pound record). Now that I'm using a vacuum system, which clamps the record even tighter all around to the platter, I would agree with that theory, as the backgrounds have gotten even quieter, and the presentation of the music even more effortless, than they were when I was using the clamp. I believe the SOTA reflex clamp works on the same principle; haven't seen a VPI clamp. There is a school of thought that a clamp is bad for the sound and the use of a felt or other damping mat is all that's appropriate (Linn and Roksan, I believe, follow this view); perhaps that makes sense with certain types of platters, but I haven't found it to be the case with at least the Basis and Well-Tempered tables I've owned. I would ask the manufacturer of your turntable what their view is, as they've certainly designed their table with this thought in mind.