I had a set of slate roofing tools since I was in college. I actually did some roofing work and helped an uncle replace slate on his roof. Thirty years later, I replaced a slate roof on a small shed. My wife and in laws were in awe, not just that I knew how to work with slate, but that I had the tools to cut the slate, put in the nail holes and even the slate nail cutter for removing the old slate. A nearly lost trade these days. I was given a cheap 3/8 inch Black and Decker drill when I was about 25. I still use it, although the cord is such a hassle compared to the new cordless models. I also have a huge half inch old aluminum case Millers' Falls portable drill, the cord is going bad on it, but it works great. That drill never bogs down. I don't use the big boy frequently, but I use it probably once a year. And usually, it is just the right tool for the job. Some times, a 3/8 inch drill or cordless drill just doesn't have the capacity or the oomph.