Looking  out  your window, you don't want to see a meandering screw line. After a while you pretty much don't see it at all anyway, but it should hold up to a close examination. What's worse is having the nail heads lift up every winter. Make sure you get screws or hidden fasteners.

When the screws are put in straight with a chalk line, they become part of the floor pattern, much like knots, plugs or seams in interior hardwood flooring.  After a couple weeks, since the screwheads are countersunk, you really don't even see the holes as the wood partly puckers around the opening and the color becomes more uniform.