I ordered two of these in unpolished White S&F and tried to fit them on a figure. Unfortunately, the axles were too big to fit into any axlehole or pinhole I tried, so I had to superglue some cut socket pieces onto them to make them usable. The pinholes seem just barely too long and a bit tight, but I imagine polishing might loosen them up, although I feel polishing could also make the piston detail too fragile.
The pieces look good, they may just need a bit of work on the connection points. An option to get them in Metallic Plastic would be nice too.