If those are 3D printed rails they look professionally done like on a high end printer. I am curious as to the letters printed on them. Some of the curves have the letter 'L' on them. Could that mean these are one side printed rails where 'L' means left curve and there is an 'R' (right) curve one too? Not reversible? Wonder what the 'O' is for since they are on both male and female end. Those Gold ones look great for a special display.
As far as the 'Long Radius Curves' go, I thought they were simply outside curves rails were you can run tracks side by side perfectly. I am not aware of any others but I am curious as you say that those are slightly wider that an outside rail.
As far as the 'Long Radius Curves' go, I thought they were simply outside curves rails were you can run tracks side by side perfectly. I am not aware of any others but I am curious as you say that those are slightly wider that an outside rail.