Bigger is better. I had two of these shelving units in my basement before ordering this one. They were 18 inches deep and offered good storage space. But this one is 24 inches deep, and that extra space makes all the difference in the world, accommodating the storage of gallon jugs of products and other larger items. I think this depth is available only in the taller units. It was expensive, but worth every single penny. These are easy to assemble. So happy with it.