"I bought this drill bit to drill 7mm steel on a canal boat. As i had already chipped three other HSS drill bits, I didn't hold much hope! How wrong i was! The ground tip not only stops the bit wandering, but helps to bore a smaller hole in the centre for the outer flutes to take out the remainder. Although the cost is quite high it will save you buying five more cheaper drill bits to do the job. At the end of the day i had drilled over sixty holes with this bit and it was as sharp as when i took it out of the sleeve. At nearly £60 for the 29 piece set, i would buy a set and save money!"