In reply to WhipperSnapper:
I have both a Fuera smock and a Fuera jacket. The smock, well my one anyway, is not helmet compatable but the jacket is. Wind proof, but depends on what you mean by light showers. Light short showers fine as long as you have kept the DWR topped up, but not anything sustained or heavy.
Remember it is basically the same material as the outer of all the paramo waterproof jackets and it is the combination of outer and inner fabrics that gives them their waterproofing. The windproofs by themselves are not designed to withstand that much water and certainly do not. Of course if you wear it over one of Paramo's mid layers, it essentially works like their waterproof jackets, but not quite as good.
I have never climbed in my paramo windproofs and so can't comment on durability for climbing chimneys. That said I have used many times a Paramo Aspira smock in the Cuillin, Skye, including chimneys and it survived all such experiences except for minor surface scrape marks, if that is any help as a comparison.
BTW if you decide you want the Fuera, my smock in black, large, is for available as surplus to my needs!