No-one ever tore 1 of these down, so it was time for someone to do it. It might be disappointing, but
that's all there was in this $40 model. The $200 models are probably the same. There might be some difference in the head travel distance & the quality of the motor.
There's no weight besides the motor. The motor has no ventilation & overheats. When the case gets warm, the motor case is over 120F. Despite this, the mane problem the reviewers have is the plastic transmission breaking. No reviewers had it break directly from overheating.