They are great sets. I would worry there would be lots of small splinters coming from the holes with plywood, at least with pine it looks like it would be an issue. Do you use pine or poplar or birch or bamboo or something else? Thanks.

Your instinct is right - pine is just too soft for this, and I would expect the holes to splinter.

I used oak plywood, and it has held up well so far, including in our kitchen. You do get the occasional tiny splinter, but nothing serious.

The main trick for getting clean holes, especially on the back side, is to drill into a sacrificial board so the exit side stays supported.

If helpful, here's a close-up photo: <https://files.virpo.sk/pegboard.jpg>