M y father-in-law has one, and I borrowed it, and to be honest, with its Heath-Robinson tubes and wires, and the maul of heaving it about, I would have had a professional in, and saved the bother. I won;t be borrowing it again!
Pay up and smile, get a pro in, and a pro job done.
It depends what you want. It's good considering it only costs �20 to hire, but you don't get professional results. You get a noticeable improvement though.