It’s really a badly marketed product. Its real utility isn’t that it uses less oil, but that it cooks incredibly fast. Essentially an oven on steroids.
It’s made cooking so much easier. I usually toss some boneless chicken in with a light coating of soy sauce and cornflour. While the chicken cooks, I prep a basic Asian sauce on the stovetop.
The chicken and the sauce are both done within 10-15 minutes. Never have to check on the chicken (unlike a pan) or wait too long (unlike an oven). Mix them together and dinner is ready.