I had to get a bunch of shelf-pin holes in the current cabinet I'm building. I used to use a piece of pegboard. a drill bit, and some masking tape. I threw out the particle board when I moved. So I looked into something a little more professional. Kreg only did 5mm and I have a bunch of 1/4" supports in stock. Rockler had a bunch of options, most of which need a special self-centering / depth stops. Well, then I found this one on half-price sale for the price of one of the drill bits. And it works for both 5mm and 1/4" pegs. It also seemed to make cleaner holes with my mortising bit than with the drill bits.
Used it today and did 140 holes, 5 at a time.
https://www.rockler.com/rockler-shelf-pin-routing-jig