I've only seen specific branded screws in 30+mm for Hardibacker boards, but they seem a bit long for some installations. However, some other basic screws don't always seem to finish flush on the surface.
Am I missing a trick here? Should any screws really suffice?
Whitebeam, could you post a link to the turbo screws from Screwfix. I normally get the Hardie screws from Topps and they cost a fortune. Quite a few of them have damaged heads too. Cheers Sean