Having a landscaping company that installs low voltage lighting, irrigation systems and various other outdoor plumbing and electrical needs I can attest that in some cases a tool like this can be valuable. However in this video its important to notice that the irrigation system is running, and as easily as the trenching spade went in had been running for a while (as in probably a regular watering schedule). They dont like dry dirt, and as mentioned before rocks, tree roots and anything hard makes this tool useless. When doing drip systems in flower gardens i usually run a sprinkler for several hours the day before an install to use these though for half inch water lines you have to get rather aggressive when spreading the trench. I dont know how useful this would be for an average person but we have 2 and have used them and they do save a ton of time if you can use it. They are also useful for installing edging around flower gardens, both the steel and plastic. Just my 2 cents from someone who uses these.