Organic Calvary, Sudachi, Yuzu and Kabosu are all different. Sudachi is generally smaller, and primarily grown in Tokushima prefecture they are usually picked while green and not allowed to ripen. Kabosu is also picked green and much larger it's generally used in sashimi and sushi. Yuzu is the largest of all and picked ripe and it used for everything from making Yuzu Tea(more like marmalade), ponzu sauce, grated over fish and even used in Onsen or Roten-Buro. I'm not sure how interchangeable these varieties are as Tokushima is on the island of Shikoku which is generally much warmer than the island of Honshu.