Binding Screw Covers

With the binding screw covers, stick them central on the screw head lightly push down but for best cosmetic affect again use a hair dryer to mould with your finger over the screw.
The binding screw covers do give you the added reassurance that the screw won't come loose, I have never had this issue but some have and I would suggest if not using the binding covers check them from time to time.
Also this is possibly another aero gain.