Otsu-rui shochu, the "real thing" honkaku-shochu, on the other hand, has a more artisan, hand crafted appeal associated with it. The nature of the raw material can really come through, and be it soba, rice, barley, or chestnuts, each has its fans and foes. This is especially true when it has been distilled at atmospheric pressure, not forced lower pressure.
Perhaps the most interesting - and illustrious - of all shochu are those made from the sweet potatoes of Kagoshima Prefecture: imo-jochu. While the flavors can be heavier and more earthy than shochu made from other starches, Kagoshima imo-jochu offers complexity and fullness of flavor that makes it quite enjoyable to many a connoisseur.
Honkaku "the real thing" shochu is usually enjoyed straight, on the rocks, or with a splash of water. Another way to enjoy either type of shochu is known as "oyu-wari," which is simply mixing it with a bit of hot water. This both backs the alcohol off a bit, releases flavor and aroma, and warms the body to the very core. Unbeatable in winter, for sure. From experience, I can guarantee it will warm you from the core outward.
Shochu overall is enjoying massive popularity these days in Japan. Over the last couple of years, both beer and sake consumption have continued to drop, where as shochu has actually increased.