nothing wrong with being a skeptic that's what we are so i know where your coming from, but hey what the h#ll can write it off for taxes on the irs website, and on top of that you get your own firecracker maker. still waiting for the sens still in mo.. so far the engine in the old ladies car is fine, checked throttle body no signs of anything nice and shinny, plus her vehicle is the test vehicle, couldn't do that to my poor vx now until i know for sure. i'm pretty safe from blowing up the bubbler keeps everything safe if it backfires, and if not i believe our ins co covers just about everything, but it's fun filling bags up to show people what it does, boy is it loud.