Only when your tool budget has limits and you find out you wish you had spent it on another one instead of one that didn't live up to expectations.
Fein- German engineering, German made. No more power really but half as loud and half as much vibration. I can't see it being a mistake despite the price. Cheap is a relative term after all.
Someone I consider a master woodworker once told me that a master woodworker is not someone who never makes mistakes. He is someone who is able to cover them up so that no one can tell.