In my experience, the best cordless rivet gun is definitely a matter of personal preference and needs. That being said, I recently stumbled upon a gem at UK Planet Tools https://www.ukplanettools.co.uk/handtools/rivet-gun/ , and it's been a game-changer for me. Just last month, I was working on a project to refurbish an old camper van. I needed a reliable rivet gun to fasten the new aluminum sheets to the frame. I found this rivet gun, and it has been an absolute powerhouse. It's cordless, lightweight, and it's made my life so much easier.