anything harder than HSS(carbide, cobalt, and any of their alloys) is going to break when loaded sidways or when it encounters drag. they are designed to cut HARD metals like heat treated steel(taps, files, locks, tool steel) and for longevity when machining. As dale116dot7 pointed out, they are really designed for use by milling machines. you are better off buying a coated HSS bit, coated with one of the Ti compounds.
I use a small dremel cutter, the smallest round cutter they make i think.. and I've drilled maybe 50 boards without it losing it's sharpness. i would try that first. i've also used a HSS drill for a lot of holes with no loss in sharpness. I'm not sure what you are doing to dull the bits out but maybe you are running them much too fast, i run mine around 1kRPM and let them cut at their own speed without forcing them.
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