I assemble sheetmetal products. So far I used about 20 M6 screws per product. Getting the nut on is a bit fiddly. Then I tighten them with a cordless drill and hold the nut with a wrench. This works quite well, but the time has come to optimise that as well. I found these automatic rivet guns that look like they could do the whole process 10x as fast and only using one tool instead of 2. and only one positioning operation vs 4. Whats your experience with rivets?