My guess is the concave head was to help prevent tearing the paper.Actually we were putting up some drywall for my brother yesterday. On his wood studs we used nails. They were smooth, no ring shank. The box of the ring shank said they could rust. The nails he used had a concave head, so more drywall compound could cover?
Absolutely will work until they pop out later. Use the proper screws when installing drywall no matter what screws someone gave you free.I was given 15 pounds of fine thread drywall screws intended for drywall attachment to metal studs. Have drywall I want to attach to wood studs. Will they work for same?