Update 1/18 - New version uploaded. Wider, more stable clips and now compatible with 'nose plugs'.
Standard GoPro snap base compatible with both OEM and my custom mounts. It's made from scratch so is not dimensionally identical to OEM snap bases. Materials might be an issue since the arms have to flex without breaking. My PETG prints seem to work well - perhaps even a bit too flexible.
Flexible legs will have two walls at .4mm nozzle size. Stiff, brittle materials might not be able to flex appropriate to snap into the mounts.