It’s purely a personal choice and gives you total control of where you want it marked.I’m not sure back in the day there was a choice of leaving it with them.Given that they vandalised your work anyway, the last think you’d want them to do was decide where is should be marked! When I was at ECA we used the college punch and did it ourselves before we registered. It was all part of our training I suppose. I’ve always had mine at home, it’s part of the final process of making my mark on something I’ve designed and worked on for hours. I seem to make a lot that can’t easily be marked like that so thank goodness for laser marking