I have been using the Hilti bits for about a year, and they seem to last about twice as long as others (Dewalt, Bosch, etc). While you're at it, check out the umbilical battery attachment to lighten up the unit for sharp end duty. It is an excellent addition if you are so inclined. Hilti has a Kirkland or Seattle branch, Patrick Morse is the sales rep @ 425-241-0697.