I took a set to the office about five or six years ago. The bits are just for throwing away, as they wear out, they are replaced with high-quality ones. "Titanium" drills for metal have also been in a landfill for a long time, gradually being replaced by normal "cobalt" ones. Feathers are quite suitable, they made repairs, changed about a dozen doors, 22 and 32 mm were used to insert door handles, all feathers are intact. When buying this set, you need to understand that the contents, for the most part, are disposable. But you will have a good case for self-filling with high-quality equipment.