The printing cost of these should be around 10euro based on the filament price. They are sturdy enough but if you hit the table really hard they will wobble a bit (but wont break or anything) its plastic so this can be expected.
If I kept the height lower this wouldn't be an issue but I needed to raise the monitors quite a bit, it's around 22 centimetres.

I have been using these since 2021 without issues. Me and my girlfriend bumped into them quite a few times and nothing loosened or fell.
I hope u will enjoy it.
The author marked this model as their own original creation.