On the audi A8 my printed mirrors worked well, but the glue did not hold during winter. SO those should be bolter through the door panel to sure they hold in shaking.
These new effiicient car models seem to start putting the mirrors again to door panel instead of a pillar corner and I believe the reason is lower drag coefficient. all the other new cars put the leg of the mirror as low as possible and thin as possible. So you would want your mirror to be as low as possible and leave the a pillar corner a gap for the air to flow nicely
I bougth to my touareg Opel corsa mirrors, which were really cheap about 30€ per piece online.
I am hoping to see a 0,015 drag drop in my touareg which has huge mirrors at the moment.