I have also not had much luck with brazed on carbide cutters. I found that some didn't have cutting edges yet, and were basically just chunks of carbide waiting for further processing. I would take them back and ask for someone to check to see if they're ok, or if they're defective. Other than that, my recommendation is to stay away from carbide until you have played with hss for awhile.
I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-