I would say that depends on how much stand-off from the bulkhead you want - and that also depends on the scale. In 1/350 (and larger scales) the molded-on hatches are usually (sometimes) the right depth, and replacement PE hatches are way too thin. For 1/350 I just remove the raised hinge and handles detail and glue the PE directly to the remaining raised hatch. That's also a way to ensure the new hatch is properly placed. In 1/700 it would probably be better to completely remove the plastic hatch then replace with the PE, so that it won't be sticking out too far.
