For a D.I.Y homeowner these will fair well to them. However, I am reluctant to recommend them to a professional who needs reliable and durable bits. For my needs though, these bits have proved good enough producing a clean hole that was easy. I've used these to drill holes into my studs, having no problems tackling those jobs. The coating on the bit has shown light signs of deteriorating after using them sparingly for 2 years. This is why I am reluctant to recommend them to a professional. However, as a D.I.Y homeowner to do projects here and there, these are a great cost saving alternative.
I used the set to drill a hardened broken bolt out of an automobile front wheel spindle. I then used the bits to enlarge the hole for tapping. I drilled very slowly with moderate to heavy pressure and the drill bits performed flawlessly. I used the sizes from 1/4" through 1/2".
The bit set was getting a 5 star review, but because the review would not let me submit the 5 stars without narrative. HD gets an overall 1 Star for forcing narrative where none was needed and making the entire purchase much less of a good deal. Happy?
Drill bits did exactly as designed, cutting through steel and aluminum and wood cleanly. Did of course require the use of oil to prolong use of the bits, but that's standard. Broke two bits so far, and fortunately one of those had the additional same size bit. Granted it was aluminum I was drilling so how steady you keep the pressure direct to prevent stress fracturing from tilting the bit can take its toll.