The Tormek T8 comes with a full-size 250 mm SG grindstone, and the Tormek T4 comes with a 200 mm version of the same stone; both can be graded coarse for shaping or fine for sharpening. If you want faster steel removal or a wheel that never needs truing, the Tormek diamond wheels (coarse, fine, and extra-fine) are the better fit. If you want a mirror-polished edge on carving tools or plane irons, the Japanese waterstone delivers the finest finish. Every setup finishes on the leather honing wheel, which removes the burr and brings the edge to a durable, razor-sharp polish. The choice comes down to whether you want versatility (SG), speed and flatness (diamond), or the highest possible polish (Japanese stone).