Assuming Filco coating is meaning the UV-coated pad printing legends?
They hold up pretty well, but with enough use will eventually wear through and the legend may get worn. (takes a lot of typing!)
The Ninja caps however have the printing on the front of the key, so no need for coating as you won't wear the legends off.
Both are ABS plastic and will gradually get smoother with use. (Not always a bad thing, but I think most people on geekhack prefer a bit of texture.)