I will ask Mrs Weaver what she prefers. She has a powerful electric screwdriver called Walter, and loves any excuse to use it. Walter saves her from all pain in her arthritic hands.
The only problem I foresee with the screw heads method is that of change in the future. If you change to different kit, then you might end up making a mess of the wall by having to make new screw holes in the plasterboard so it ends up a mess. I suppose one way around it would be to put up a mounting board and then screw screws into that, so that if spacings need to change then a fresh mounting board could be put up in place.