Header studs or bolts?

On my small block stuff in the past, I've left the factory studs in the front and rear holes in the factory iron heads. Those hit water. The other holes, bolts. Because of twists and bends in the tube, bolts work better. Even on the al-u-minium heads, if you stud the front and back, they can hold the header and gasket while you start the other bolts.