I've bought quite a few Grizzley buts over the years and find they are mediocre, for the most part.
For a real comparison, get the same bit from Grizzley and Whiteside and take a few cuts with both. I found the difference to be outstanding. . .in favor of the Whiteside.
I find Amana bits to be a significant step above Grizzley, almost but not quite as good as Whiteside.
As for me, I've stopped buying Grizzley and only buy the other two.
YMMV
Pixmaker in FLL ========================== It's not the heat, it's the humidity! ========================== (...Think the humidity's bad? You should watch us vote!)