I have rassled every kind of grotty, rusted, worn down, spun out, grimed up and stuck by pure Time screw known to man. There are times when the only thing that works is a high-speed drill with a really hard bit to grind out the head, and a tap-it to work out the body. I don't know Robertsons by name, but having looked them up they look familiar as the design my deck screws came in (with their own square-head driver) and I have to agree with Gnu--they never gave a lick of trouble going in or coming out.