The increased speed hydroponic plants grow at compared to plants in soil is what really makes it exciting for me. A plant in my basic countertop "indoor garden" unit is growing 10x as fast as a cutting of the same plant sitting in my windowsill.
Are their models considered to be the best or is there some competition? For plant identification, they blow every other free app I have tried out of the water. It also seems to return the genus of a plant rather than misidentify the species which I find impressive.