I'm establishing various door openings in metal frame and wondered if anyone recommended any particular door liner kit as being good. They don't appear to fully standardise on the thickness of the timber and that affects the size of the reveals to be left in the metal frame stud walls. There do however appear to be lots that are 32mm nominal which equates to a finished 27mm. There appear to be thicker ones for fire rating purposes. A 70mm stud with plasterboard either side works out as 100mm, so