The junior is basically half the size of the standard unit. I plant herbs in them since many of those are cooler weather plants and I can bring them inside in the heat of summer. I also use their automatic watering system on the standard boxes.
From this point on, I am looking into getting my planting media (these are soil-less if you didn't know), fertilizer and dolomite (calcium/magnesium) locally from now on. They publish a list of approved products.
Ok, thanks for the link.