Exactly... I was checking the difference between the DJI and the cheap ones this morning. There is a VERY big difference. The DJI props are a lot stiffer than the clones and feel heavier as well. Also, the hole in the prop that fits over the shaft on the motor is a lot tighter on the cheap blades. I really don't think that it can be good for the motors when you're pushing and pulling hard to install and remove them. One thing for certain is to never use a combination of both when you fly. Actually, I don't think you would even get off the ground if you tried to do this.