I'm very fond of Wood Designs. We now own 9 of their bookcases in various sizes. I think they build some of the best values in book shelving on the market. It is always well constructed, and handsome. The clear finish and exposed plywood edges fits well with out mid-century modern home. It is much more durable (and sag resistant) than comparably priced IKEA shelving units. Though finished on the reverse, it does have a reinforcement (made of the same plywood material), about 4 inches tall and stretching from side to side, midway up the unit.