Used ittoday to drill a couple holes in the bed of my truck working on a project. One was in a reinforced spot and had no issues going right through. Didn't use a punch and didn't have an issue with the bit walking but mostly because the sprayed bed liner helped.  Only a few holes in sheet metal and some 3/16" thick aluminum but seem to hold it's cutting edge well. Time will tell on longevity but price was good enough for me compared to much pricier bits.