Japanese knives intended for home use are not that long. Keep in mind housing tends to be smaller, kitchens are likely smaller, etc, than the American standard, and there isn't as much room to bang around a giant knife. Santoku, nakiri, funayuki, bunka hocho, and other such knives are rarely more than 180mm. Even usuba and deba, which do come in a great variety of lengths, are available in those sizes, too. However, as I understand it, the single bevel knives are used mostly in a professional rather than a home setting. If you want a long blade that will slice its way through vegetables at lightning speed, you're better off getting the "laser" variety of gyutou, such as those made by Konosuke, Suisin, and others. You can get them anywhere from 210 to 270 mm.