I love these drills. When prepping with rivets it's important to get the wires where you need them and overall these bits are fantastic. They will pierce nails or screws easily enough that you don't even realize you hit one of them. In fact, I've used the file more times than I can count to return those bits. However, you will need to put some force on the drill from time to time to get through. And I can honestly say these bits have lasted until yesterday whether I used them in my regular drill or in a punch. However, yesterday I was disappointed to find that the quick release part in my drill bit had broken off. First day of using the new 1" bit I bought to replace the one that had frayed threads after a year of use and abuse. I still love these beats in general, but I'm very disappointed in this particular situation.