The 406 coupe cup holders are not great - really small and ideally placed to knock over with your elbow when changing gear
If we can expand the topic to door pockets generally, think the Coupe ones are pretty terrible
Looks huge on the picture, but really quite slim (sunglasses in case take up full width) and pretty deep, so if you drop a pen you have to drag it up the side to get it back. And when you take the door lining off there's plenty of space, could have been a much bigger pocket
Matt
Mind you my wife's 3 door 206 has some door pockets that you can't get at with the door closed which isn't great either!