I now still have the have the original cheap blade in my little Kobalt saw. 10". The greater the diameter the greater the surface speed. So while the motor goes at a constant speed the 10" blade will have a greater surface speed than a smaller blade. Same as on a lathe, mill, drill or saw. Perhaps the difference is negligible but it is still there. I'll continue to use my new 10" Diablo blade when it arrives to0morrow. No argument here. Just stating an opinion. But what the hell do know?